I assume that the Optimization mod works the same as other mods--people can't join unless they have it enabled and if you have it enabled you can't join games without it, just as with custom maps.
However, if it really works, then I'm all for it. We just need lots of regular players to get on board.
Unfortunately, they put the file up at what appears to be an awful place. To get the file you have to register an account and then you're limited to 150 mb/hour (the file is 196 mb). My visceral response was, "No thanks". There's gotta be a better place to put this file, somewhere.