You can't legislate morality. A trite statement, you might say, but you can be certain that abuse every loophole they can. After all, the mangling of IE into Win98 exploited a loophole. Even after being declared guilty, they still use bundling and restrictive licenses. You could say that this is unavoidable but still limits their behaviour. But Windows is such a powerful asset, any small abuse of this has a large effect. The trust busters will have to go back to court each time and by the time consent decrees are amended, the damage has already been done.
Only structural change will do.