All right, I'm back in town and it's time to get cracking on some feedback. I'm going to be replying to concepts in the order they were posted provided they were in the correct format. If I respond to your concept and you edit it and request additional feedback, shoot me a PM. If I didn't reply to your concept, it's because I saw it as a heavy work-in-progress and I don't want to judge it before it's all finished.
Salt the Flesh (Low Priority) - This is an interesting concept, but I worry that there are already Pokemon that handle OU's priority abusers rather well. You mention that this concept doesn't have to be a Physical wall, but it's pretty clear that Talonflame and Mega Pinsir can get past just about any Pokemon not packing a ton of Defense. Furthermore, do you think it's possible to even semi-reliably counter Talonflame, Mega Pinsir, Aegislash, and even Azumarill with one Pokemon? Most defensive Pokemon handle priority users the same way they handle offensive Pokemon without priority, and it'd be pretty difficult for an offensive Pokemon to handle your concept. I'm not sure why a Pokemon dedicated to handling priority needs to exist in this metagame when so many Pokemon already (Rotom-W, Hippowdon, Mega Venusaur) can do well against many (but not all, admittedly) priority users.
Quanyails (The Safety Net) - I am a fan of this concept. It seems like this concept wants to create a universal "glue" Pokemon role in that it can be stuck on a team and serve some purpose at least once in the match. There are examples of this concept in past OU metagames, such as Scizor in Gen IV OU (could usually do 60%+ to a Pokemon you let set up against you) or Alakazam in Gen V OU (Focus Sash = one, often two, guaranteed hits). Do you think a Pokemon like this already exists in Gen VI? I'd argue Alakazam can still serve its Gen V safety net-esque role, but Alakazam really isn't the Pokemon it once was. I'd like to see this concept explored, and I think there are quite a few ways to go about this. I'd like to see a few examples of where you might want to take this concept, if you don't mind.
nyttyn (Power for a Price) - I'm not sure what "sacrifice" means in your concept. As you said, "Sacrifice" could mean the sacrifice of a Pokemon, a quantity of a Pokemon's health, in-game momentum, or something completely different. Also, how would you mandate a Pokemon to be better after a sacrifice than before the sacrifice? I'd like to see this concept be narrowed down some more, at least let me understand what kind of sacrifice you're talking about and how you intend for a Pokemon to be
better after something is sacrificed for it.
loco1234 (Backlash) - I'm not sure how you turn something that's inherently bad, recoil, into an advantage. Although low-HP strategies certainly have existed throughout the generations (Endure+Reversal, Pain Split, etc.), very few if any of them rely on recoil (damage you take from yourself) because recoil damage is unpredictable. You don't control how much damage you take from recoil (besides Life Orb), so you can't whittle your health down to exactly where you need it to be. Without examples as to how recoil damage
specifically can create an advantage for the user, I'm not convinced this concept is feasible.
Unitas (Never Seen Before!!) - I think that every CAP, we're trying to create something that hasn't been seen before. Arguably, that's the whole purpose of the CAP Project. Looking at our most recent creations, Cawmodore sweeps with a move that was barely ever used in Gen V, Malaconda used an ability whose potential had gone unrealized, and Aurumoth was probably the most powerful two-pronged attacker in its generation. This concept really doesn't give us much to go on; we need something more specific than "Never Before Seen" to move forward with the project.
EpicUmbreon29 (Vantage Point Creator) - This is another concept that just seems really nebulous. Of course every Pokemon exists for its user to gain an advantage, for the balance to be tipped in the user's favor. You mention everything from Frost Breath (a move never used, and for good reason) to multi-hit moves (which are rarely seen without Skill Link, again for good reason) and it just seems that this concept tries to make a "jack of all trades". Your explanation just seems like a list of moves that are either already pretty well-explored or outclassed in nearly all situations. If you could list some specific vantage points you're trying to make, I think I'd understand this concept better.
The Pizza Man (Nostalgic Playstyle) - I like the concept a lot, really. What this concept lacks in ambition it makes up in feasibility and interest, especially since there are dozens of metagames to choose from. I'd like to see some more explanation to this concept, such as certain nostalgic playstyles that you'd like to see explored. I'm not sure what you mean by "What is the definition of viable" in your questions section, either. If you clean up the Questions and Explanation section, then this concept shows a lot of promise.
Kankuro195 (Ability Neutralizer) - How do you see us going about neutralizing opposing Abilities? It's pretty evident that Pokemon like Medicham and Mawile are significantly worse without their Abilities, but most teams have 4 or 5 Pokemon that can function fine without their Abilities and a Simple Beam spammer isn't going to revolutionize the metagame. Pokemon like Excadrill and Kyurem-Black already show how some Pokemon like Rotom-W and Latias need their Abilities, as well.
Mowtom (Hazard Control) - Can one Pokemon be a universal hazard controller? Each hazard and hazard-clearing move takes up a moveslot, and a universal hazard controller (I assume like Forretress in the past two generations) will end up with some pretty bad four-moveslot syndrome. I think this concept does have some promise, however. Pokemon like Skarmory in the current generation try to accomplish this role, but I'm not sure if having hazards and hazard-clearing moves on the same Pokemon is that significant an advantage. I'd like to see a little more explanation on that front.
ghana.7 (One Mind) - There are a lot of Pokemon that you see only run one premier set in this generation as well as previous generations. Conkeldurr is always an Assault Vest tank, Mega Pinsir is a Swords Dance annihilator, Mandibuzz is a bulky Defogger, etc. If you have a specific, perhaps unexplored, role in particular you'd like your concept to explore then I think it would be more fitting for the CAP. But right now, "very predictable Pokemon" is a role taken by many prominent OU threats. Not to mention it's not a particularly interesting concept. There's potential with this concept, but it could use some more specificity.
Xlelius (Ultimate Baton-Passer) - Baton Pass isn't a bad idea, but there are a lot of more pressing changes to Gen VI that seem more worthy of exploration. If Baton Pass is popular enough then it'll be worthy of inclusion, but Baton Pass has already had its time in the sun.
Fuzzie (Universal Tank Buster) - This is a pretty cool concept. Tanks are definitely prevalent in this metagame; Pokemon like Conkeldurr and Tyranitar are masters at taking hits and dishing them out, and most battles spend the entire mid-game busting through the tanks that handle sweepers. A concept like this, if executed successfully, could have a lasting impression on the metagame. Although being threatening only to defensive Pokemon (or primarily to defensive Pokemon) could be difficult, it's a worthy endeavor. I'd like to see some more examples (outside of a clearly niche FEAR strategy) of how you want to bust tanks, but this concept is very promising.
TitaniumWall55 (Return of Weather) - I don't think it's fair to say weather is nearly extinct; it's just returned to the same level of viability that it had in Gen IV. Sandstorm is still as prevalent as ever, and Tyranitar and Hippowdon are defensive stalwarts that need to be covered by any competitive team. Furthermore, "return of weather" is a pretty vague concept; could you go into detail about which weathers you believe are possible to promote and what you believe makes weather so much less effective in this generation?
Dr.Slugma (Electric-Stopping Jack of Trades) - I don't understand why stopping Electric-types is so important specifically. The only relevant Electric-types in OU are Galvantula, Rotom-W, and Thundurus. Although those Pokemon are nothing to sneeze at, they need an entire CAP dedicated to stopping them. A "jack of all trades" Pokemon is definitely interesting, but the Electric type is not prevalent enough in OU to be worth an entire CAP. In Gen V, the Dragon type was good enough to be worth dedicating an entire CAP, as was the Water type. In Gen IV, there were entire metagames that revolved about stopping perennial powerhouses Salamence and Latias. Those metagames were so dominated by a single type that it merited a CAP, but Electrics in the current meta are not threatening enough to merit a CAP.
PikapowerUltra (Stats and typing vs Abilities) - This is really two concepts in one, but I don't think either concept is specific enough to be considered for the CAP. There are Pokemon with hindering Abilities and Pokemon that are redeemed by their Abilities, the same goes for stats. Trevenant has pretty poor stats, but its abilities and synergy with Mega Charizard Y makes it a force in OU. Aegislash is a Pokemon with pretty medioocre stats and one of the best Abilities in the game. If you can specify exactly what sort of Pokemon you want with this concept, it'll be easier to consider it moving forward.
shockwave527 (Pilot Fish (or Scope Out)) - This concept is essentially the ultimate scout, much like we did with Kitsunoh two generations ago. With the banishment of Genesect to Ubers, OU has lost one of its best scouts. Although OU definitely has its fair share of scouting-based Pokemon (Rotom-W, Greninja), there isn't a dedicated "scout" Pokemon in OU. I'm not sold on the explanation of this concept, it's not going to be possible to create a scout Pokemon without scouting-based moves. To determine the opponent's sets, you need specific scouting moves because forcing switches isn't enough. I like this concept, and would like to see it move on if the explanation is improved :).
Yilx (The Big Dipper) - I can get behind this concept, it involves identifying the best cores in OU and finding ways to destroy them. Although Kyurem-Black is already a great example of this, we can create a Pokemon with more of an "OU build" that can take down other prevalent cores. I don't think we need to go the setup route with this Pokemon (Kyurem certainly doesn't), but that should definitely be on the table. The only reservation I have about this concept is how many Pokemon already sort of perform it already; all of the examples you mentioned are pretty relevant to Gen VI OU. Do we need a CAP to learn about the Big Dipper, or can we learn about your concept by studying the current metagame?
TRC. (Why so slow?) - Sticky Web is definitely OU's elephant in the room. I don't need to be convinced of Sticky Web's viability, anyone who's played the current CAP metagame knows Sticky Web Necturna is a terrific support Pokemon. The only relevant Sticky Webber in OU is Galvantula, and it's no secret Galvantula is no OU powerhouse. Although the prevalence of Defog could be a thorn in this concept's side (not to mention that it would be the second "underappreciated move" CAP in a row), it's only one obstacle to overcome. It seems you already have a pretty great battle plan for accomplishing this concept outlined in the explanation, as well. Impressive :)
Dummy007 (Major Third) - A more complicated Perfect Mate? Many concepts submitted during this round have been about studying offensive or defensive cores, and this concept seems like a great way to do so. Voodoom's concept taught us more about the late DPP metagame than we expected it to; we tried to create a great core and ended up creating a different amazing core. Major Third could have the same pitfall, but just like Perfect Mate we'll definitely end up with a great lesson about the metagame.
senshidenshi (Movin' Out!) - Although this is a cool concept, we just finished a CAP in which we explored an underappreciated move (Belly Drum) that also let us explore Acrobatics as well. This concept is definitely worth exploring, but I'm not sure if it's the right time right now. So many moves like Storm Throw and Fell Stinger have the users to make them viable, but are simply outclassed by better moves. Technician is definitely a good way to boost underused moves, but it's also been done to death by Pokemon that already exist. There's promise here, but I'm not sure if two straight "underused move" concepts is the way to go.
ZirconSubway (True Persistence) - This concept seems like "build a really great Pokemon", I'm not sure what we learn by building a Pokemon that just hits really hard and takes a lot of hits. I don't think the Cinccino line is an appropriate example, as Cinccino is a rather frail Pokemon that cannot take the hits the way your description describes. Mega Heracross is a better user of Skill Link, and it's definitely not doing 3% with Rock Blast to anything. I'd like to see something more specific than "Pokemon that takes a lot of hits", but less specific than Skill Link abuser. There's something there with this concept, but it's unclear right now.
Vryheid (The Robber Baron) - There are definitely tools such as Punishment and Heart Swap that can turn an opponent's strategy against them, but so many of those moves are niche even though the abusers are there. Me First was discussed at length during the previous CAP, as was Power Split. The only potential problem with a "toolbox" Pokemon such as The Robber Baron is that some of the moves you outline (Power Split, for example), require significant bulk to use effectively. Power Split and Me First are also very easy to play around, the latter move even lets the opponent switch without penalty. I like this concept, but I would like a little more explanation directed at its feasibility.