I actually love that idea! I think it has even been brought up in the Policy Review thread. The only issue is that it is more complicated than Aldaron's proposal, since we are now banning a combination of Drizzle and specific Pokemon, but the difference is negligible. This proves to be a good alternative for Rain that passes Phase 2. I will go edit this into the OP of my proposal thread! Thanks, Lightning Tiger!
I hope you can now better appreciate this approach, LTiger. Please take a look and contribute to the thread: http://www.smogon.com/forums/showthread.php?t=85113
The idea is bad.
It's one thing to say "Two abilities are broken together" It's another thing to say "Two abilities are broken together on 6 pokemon so we stopped 6 pokemon from being used on a team where the other ability is present, and left everyone else with that ability allowable to use with the other ability."
Combination restriction of abilities I can get, that restriction based on specific pokemon? This is getting too much.
I still say 6 pokemon is nothing in the grand scheme of things.