But the thing is, the problems facing lostgar aren't bizarre techs that aren't going to see much play. For the most part, they are commonly played cards meaning that you won't be able to just take 1 or 2 losses in a tournament. If you get lucky with your matchups, maybe, but not for the most part.
I think it'll deffinately even out the playing field, if anything. As it's been said before, the more you tweek to counter LostGar, the more inconsistant your deck in toher match-ups becomes. So you have one dark counter against LostGar? This may not save you. If you have two you start taking up enough space that it could cost you the game in a match against soemone who didn't worry so much against LostGar.
In a big tournament, who knows what will happen? Who knows who'll knock who out? Even a 1-1 line can make difference in consistancy against a deck you don't need it against, expecially if you start with it.
I think the best counter to LostGar is to know the deck and not worry to much about straight counters to it, or you'll suffer to someone who didn't. Then again, there is always Junk Arm.
Can someone post an SP deck list to counter LostGar? Now, what if you run into VileGar? SP has some issues with VileGar as it is, would teching against LostGar even it out for VileGar?
As someone has already pointed out, Chenlock is probably the best idea as it already counters Vilegar.
VileGar will be even in stronger in the next format as Rare Candy is nerfed and it half of the time doesn't care about going first or second agaisnt a trainer heavy deck.
Really I think that all you'll have to do is know LostGar and it'll be a good match-up. Don't hypervenolate when you're already preparing yourself.