[Remedy]

Originally Posted by Fat NixHex

edit: somewhat ninja'd by RapidChipmunk

I don't think that's his point. If it uses Superpower hoping to hit Weavile and it isn't Choiced, why wouldn't Scizor just use Bullet Punch to prevent this from happening? Personally, if I were using a non-Choiced Scizor, I'd just use Swords Dance since Weavile is basically giving it a free turn to boost and just annihilate Gengar altogether with +2 LO Bullet Punch.

Also adding onto what kd24 said about its frailty and stressing a point I made in the OP, Weavile's inability to do much damage to set uppers like Scizor and Jirachi as well as hazard layers like Ferro, Forry, and Skarm (assuming you aren't running Taunt) gives them free turns to do whatever they need to do. Also, Dragonite with Multiscale intact can actually set up while Weavile uses Ice Shard and then just kill it with ExtremeSpeed. Here are the calcs that spell Weavile's doom:
252 Atk Life Orb Weavile Ice Shard vs. 0 HP / 0 Def Multiscale Dragonite (Multiscale intact): 53.25 - 62.84%
252 Atk Dragonite ExtremeSpeed vs. 0 HP / 0 Def Weavile: 96.19 - 113.49%

Even though you can't OHKO without Ice Punch, my point is that Weavile cannot revenge kill Dragonite with Ice Shard, and will almost always die before it has a chance to do anything.

I don't understand your Calc, I'm pretty sure there is a mistake somewhere :\
252Atk Dragonite (+Atk) ExtremeSpeed vs 0HP/0Def Weavile (Neutral): 49% - 58% (140 - 165 HP). Guaranteed 3HKO. 25% chance to 2HKO.
252Atk +1 Dragonite (+Atk) ExtremeSpeed vs 0HP/0Def Weavile (Neutral): 74% - 87% (209 - 246 HP). Guaranteed 2HKO.

So if SR are not up, you can revenge the Dragonite ;p
252Atk +1 Dragonite (+Atk) ExtremeSpeed vs 0HP/32Def Weavile (Neutral): 70% - 83% (199 - 235 HP). Guaranteed 2HKO.

This is when these 32 EVs that nobody seems to care about come handy, even if in my opinion you should put them in SpD mainly for that :
252SpAtk Life Orb Starmie (Neutral) Hydro Pump vs HP/32SpDef Weavile (Neutral): 83% - 98% (234 - 276 HP). Guaranteed 2HKO.
But they are also useful to survive a ScarTios Draco Metor at full health. To not be 3HKO'd by Scald from Tentacruel, and not 2HKO'd under Rain, to not be 3HKO'd by Jellicent scald etc...

For the Dragonite case, you should just ALWAYS have SR and some Spikes when you play Weavile, else he won't be so useful.

And I don't know why there is Ferrothorn in the least of spikes that can't be hurt by Weavile,
252Atk Life Orb Weavile (Neutral) Low Kick vs 252HP/88Def Ferrothorn (+Def): 50% - 60% (178 - 212 HP). Guaranteed 2HKO.
A 2HKO on Ferrothorn for a Physical Sweeper is something quite decent in my opinion.