here's why i think crobat is a bad idea:
1.) Demeaning past suspect tests - We came to a supermajority that Crobat was BL and by our own rules, once that happens, the Pokemon stays in BL. If we are just gonna bring down stuff again just for the sake of retesting it to see if its still as strong as before (especially when a lot of people are already saying it will be banned again anyway), then why are we having these suspect tests and nominations? It casts doubt over the whole process and makes it seem its really just a free for all. Had we addressed bringing back a pokemon earlier because of apparant metagame shifts, fine, but after everything thats been done, we are moving forward in uu with a positive light. Look at the 2 most recent nomination threads, no suspects dominated the last one and its definitely dominating this one. The metagame has balance, people are happy, and talk of "not enough people are playing" is silly, there are more than enough to have diverse games, all of that silliness of testing gimmicks has basically worn off, and we have a stable foundation for uu. Sure, unbanning Crobat might bring back a few players immediately, but they will likely just leave after a few days of testing and we are stuck with another broken mon and more bitching.
2.) Crobat is still going to be the same exact problem it was before; A Pokemon that can act as fast sweeper, defensive stronghold, and all around momentum stealer in any game it plays. It is able to fight and defend a large number of Pokemon (with the same set). Take a look at the top 10 UU Pokemon:
Venusaur - Crobat is a top 5 counter, maybe not number 1 because of being susceptible to Sleep Powder. Crobat is going to Brave Bird / Roost up all day vs Venusuar.
Milotic - Crobat doesn't win but it doesn't really lose either to one of the best walls in the game. It can Taunt it's recover and then just U-Turn out to a Venusaur, Chansey, etc., causing Milotic to not be able to regain health and have to lose more to Stealth Rock / Spikes. If Milotic is Toxiced, Crobat can come out on top here.
Mismagius - Has to Sub/Tbolt the switch-in, Brave Bird is doing a ton, defensive Missy is shut down by Taunt/Roost/BB. Missy isn't the worst Pokemon to fight Crobat with, but being slower really sucks. Crobat is an excellent check to Missy though.
Spiritomb - Does even worse than Missy, Crobat's Taunt shuts down healing/status, while you can Roost vs Sucker Punches or weak Shadow Sneaks. I would just U-Turn or switch out afterwards, assuming he doesn't switch.
Registeel - Regi's only hope to actually win is Explosion, otherwise, Crobat is just going to Taunt, Roost, and U-Turn to a better match-up. Ice Punch/Earthquake could damage Crobat but that is just a bad moveslot desicion for Registeel. Registeel just can't do enough and so Crobat acts as an excellent check.
Arcanine - Arcanine is a pretty big threat to Crobat, and both take 25% from SR. I'd argue that Arcanine is the safest Pokemon to bring in so far, although it can be pretty risky.
Uxie - Crobat can Taunt/Roost/U-Turn > better match-up, in the meantime damaging a valuable wall. Uxie can hit pretty hard though.
Alakazam - Crobat outspeeds and OHKOs. Crobat can also switch in on 3 of its attacks (yes, even sub as it can just u-turn out to pursuiter). Crobat checks him perfectly (just don't be stupid and come in on Psychic).
Rhyperior - Crobat loses 100% straight up, but you have to think this through. Let's assume early Player A has Venusaur, B has Crobat. Player A is going to switch, the threat of Brave Bird or Taunt is going to force Venusaur's hand. Player B just wants to scout the team for now, having other methods of winning if Venusaur somehow stayed in. A brings out Rhyperior, B U-Turns, out comes counter, no momentum lost and the pressure is back onto A. This sort of pressure is commonplace with Crobat, whos healing, Speed, bulk, typing, etc make it almost impossible to take down until much later in the game.
Houndoom - Neither should switch into the other, but Crobat wins with Brave Bird and faster Speed.
Crobat loses straight up to 1 of them - Rhyperior
Crobat basically ties vs 3 - Arcanine, Milotic, Uxie
Crobat wins or acts as a perfect check vs 6 - Venusaur, Mismagius, Spiritomb, Alakazam, Houndoom, Registeel
Against the 4 you either lose or tie with, weaknesses to Toxic and Taunt plague them. If you can get Toxic Spikes on the field and then keep Toxic Spikes absorber at bay with Crobat, you can virtually stall out most of the game. Toxic Spikes absorbers include Venusaur, Toxicroak, and Drapion - standard sets are not beating Crobat.
Crobat has counters, yes. Any Pokemon does - but Crobat can basically force their counter's hand early by being such a threat to other Pokemon and still U-Turn out when the counters come in. I really don't want to lose to Crobat because my "check" or "counter" got toxiced by like a Registeel or something. That shouldn't happen, but Crobat's unique stats allow it to. Finally, add in Crobat's defensive prowess here along with the fact that it can just sweep a large amount of Pokemon thanks to Brave Bird and 130 Speed while checking many more (moltres, blaziken, clefable, etc) thanks to Roost, Taunt, and Brave Bird, and you can see why I'm very much against allowing Crobat back in.