Sandstorms nullifies leftovers, but Stealth Rock only hits when I switch, and Dragon Dance isn't that useful if I'm dancing around. Liberal Use of Dragon Dance means about 3 or 4 at which point you are faster then a scarf'd Deoxys-S,and there are not counters, there are OHKO's
Even though D_A covered this, I just wanted to point out that you're going to have to clarify what "liberal use" means in the future (and similar descriptions) because it's just way too broad to give us any idea of what you mean.
And yes, it's sort of a given that if you let something set up like crazy, it's going to sweep you lol.
I usually just abuse Trick, Explosion, and powerful attackers. It's nothing too specific usually, but stall teams tend to fall apart once Blissey dies, as it IS the most heavily relied on member on almost any stall team. And yes, I know Blissey carries Protect a lot. That's why I bait it into a false sense of security by not blowing up the first time I see a bulky pink blob opposing my Gengar lol.
Also, I totally disagree with D_A's assessment of Outrage Salamence not being able to beat stall. As a user of CBMence, I can tell you that the pressure is always on the opponent to pick the right switch-in, or he or she basically loses a Pokemon (whether or not it dies...40% Hippowdon isn't going to wall much lol). Even in the OP it says that no one Pokemon can beat stall, so writing off Outrage Salamence is kind of silly IMO, especially when stall teams become very vulnerable once even one member is dead. Salamence doesn't have to kill everything on its own, and in my experience it's a much more deadly sweeper than Infernape could ever dream of. Infernape has Toxic Spikes/frailty/Life Orb recoil being stalled out/inability to switch in on ANYTHING issues. D_A, I know you hate New MixMence to death, but as long as you use it correctly (in other words, you just switch out of Blissey and predict it coming in next time Mence is in--not that hard once you get used to playing with New MixMence), it's easily one of the top 5 or top 3 mixed sweepers in OU. As far as beating stall is concerned, it really is a great finisher with Draco and Outrage. That's something Classic MixMence can't really do at all, and it makes him a useful asset.
Beating stall for me is all about finding what sweeper has the best opportunity to win the battle and then weakening or eliminating its checks and counters. It's pretty easy to overwhelm stall teams really, but if it's played really well, they're always pretty annoying to beat...but certainly not impossible. I basically always beat ObiStall though since...it totally sucks? lol