I think it look like:
Instead of paying $2/hour plus tips over which an 8 hour shift averages out to, make up a number, $20/hour. You pay $20 an hour and add 25% restaurant management fee to every bill (or whatever you want to call it, it goes straight to the management costs). No different than the "resort fees" you see at Vegas or Hotels. Or "delivery fee" you see with food delivery, etc. These aren't real fees to cover anything other than management costs.
Like I said, it's six one way, half a dozen the other to me. I'm paying the same regardless (X * .25), so might as well architect the way that best helps the workers and restaurant management.
Will you lose people who don't want to pay 25%? I have no idea. I've never been someone or known anyone who stiffs waiters and doesn't tip. Is that a sizable contingent of people who dine out? Is the restaurant industry built upon those people? Then the $2/hr strategy is a bail out for those losers, if so, and another reason to squash it.
I say all this now, but let me get hit with bad service from servers with bad attitudes because they are not incentivized to do a good job (read: like every other retail worker in America) a couple of times and I bet I'll change my tune. I know me too well.