I'll just say this: given the ever increasing number of petty, overcompensating assholes that seem to populate the world today, I am very relieved my income is not directly related to their judgment and every whim.
This isn't school. None of us are in positions where we should be "grading" the performance of our waiters and waitresses. They do their work. They should be paid. Whether or not they are penalized for doing a substandard job should not be determined by the tip they receive but by the employers who manage them.
Anyone who uses the situation of the current tipping system to "punish" their servers is just being an asshole for the sake of being an asshole.
Like I said before, stop being an asshole.
Seriously? You give a flat rate tip to every server?