In a normal restaurant situation, I generally tip between 17 & 20% with the
range extending a few points in either direction for especially bad or good
service.

To me that is ridiculous - on the bottom end. The lower limit of the range
should be zero.

If someone gives you execrable service why would you give them ANYTHING??

In my view the waitstaff is paid to do the basics - manage to get the right
orders to the right table, avoid spilling hot soup in your lap etc. The tip is
not given out of duty, it is given as recognition of service ABOVE that very
basic standard.

I agree that a waiter would have to screw up pretty badly, or have quite an
attitude to warrant no tip, but IMO you have to have a tipping range that
encompasses such egregiously bad service.

I do not do what I have seen others do and leave a quarter - petty and small
minded. But I have called the maitre'd over and explained that I was not
tipping and why.