I rarely say this, but I agree with what Firestorm had to say about this the last time it came up:
Originally Posted by Fat Firestorm
As TPCi and Game Freak start doing more and more to promote competitive battling (Battle [noun], GBU, VGC, Stadium-type games), it would be nice to keep definitions similar rather than different so that players (who will increasingly get their first taste of competitive battling by their rules) can come into ours without having the definition of the clauses completely changed on them. Especially if we're moving towards a "good enough, let's play the damn game" approach rather than analyzing every single aspect of our ruleset to attempt an unachievable "ideal" metagame.
I really see no benefits of trying to change this either, there might not be any big downside to trying to hammer something out here, but there are bigger and better things that Smogon still needs to focus on atm.
You can obviously still do a tournament to try something like this out, nothing wrong there. Just don't expect whatever conclusions come out of it to actually change the Clause as it is.