I was disputing the notion you have no obligation to pay a tip or table minimum which is disclosed ahead of time - you do have an obligation, although you can certainly make a case to management if your service was subpar and hope they adjust it.

If the tip was not disclosed ahead of time and just showed up on the check, as I posted above I would (assuming the service wasn't worth the tip amount charged)

1) call my credit card company, explain I was being compelled to sign for an amount different than indicated in the menu pricing and ask for guidance on how to handle the receipt so I could dispute the overage after leaving

2) pay with cash and leave just enough for the total, tax and any gratuity amount I felt was reasonable, then leave the restaurant

Actually, the best advise is to avoid those over-priced tourist restaurants around Miami that practice this and stick with quality restaurants that receive good reviews and actually offer good service and quality food. There isn't a single restaurant in all of South Beach that is truly worthy of my dining dollars except for Joe's (in season) or maybe Books and Books Cafe for lunch; although for giggles, I suggest Next Cafe (they usually DO add a service charge) to see how a former cook at Cheesecake Factory was able to walk out with their entire recipe book and recreate the Cheesecake Factory menu (literally) and survive the resulting lawsuit.