Do I have to explain this a fourth time? As long as you are in a double battle with a Pokemon that can learn Skill Swap and another Pokemon that has a "bad" ability, use Skill Swap on the Pokemon that has the ability, then Skill swap again with the opponent! This can devastate enemies such as Reshiram, zekrom, Bisharp, or any Pokemon with a good ability. So, no ability is bad if you can use it right! Does no one read my posts?