Crobat seems to me to be complete ass in every way possible. Let's look at some of the reasons people think it's usable.
Ah Infiltrator Brave Bird. That seems useful. Except that realistically what is using sub at the moment? Gengar? Ok good one thing Crobat can check...well unless it gets burned by WoW. Fast Taunt is useful, but not more useful against stall than any other Pokemon with Taunt, especially things like Stall Breaker Mew, which has, you know, actual defenses. HAze is a terrible move lol, it's not fast enough to haze away boosts on sweepers, so the only thing it does it like...Calm Mind users? Ok so it beats Sub Gengar and Suicune unless it gets burned. Nice. Defog, yeah and so do a bunch of other Pokemon with either good attacking stats or good defensive stats, of which Crobat has neither. Roost is great and all but it doesn't change the fact that it has shitty defenses which can't even be invested in because you need to take advantage of its Speed if you want it to be useful. It resists U-turn. Ok and the Pokemon that use U-turn are...Landorus, Mega Scizor, and Landorus-T? Which of those can it beat? Cause it seems like all three can beat it pretty easily. Fighting resist lets it beat Keldeo, Terrakion, Breloom, and Conkeldurr as long as they only run mono-attacking sets and we pretend Specs Scald, LO Stone Edge, Rock Tomb, and Ice Punch don't exist. It's immune to Toxic. Nice, now it's shitty defense can't be put on a timer! And it counters Gliscor. Alright so add that to the list and we get Gengar unless it gets burned, Suicune unless you get burned, and Gliscor. Yep, that seems like a C+ Pokemon to me.
Alright I get that this post was probably overly hostile, but I just woke up and I'm not a morning person. Also I can't stand when people advocate for a Pokemon when it's been refuted so many times. This is one of those times. Crobat is just outclassed. There's nothing it does that can't be done better by other Pokemon including Mandibuzz, Mew, Skarmory, and most importantly, Talonflame. It just doesn't have the ability to max out its defenses and its speed at the same time, which makes it pretty mediocre in all regards.
Also you went after my nigga
Gary2346 >:c