Great article. The one thing I would add is don’t be afraid to ask. When I’m unsure about whether to tip, I just ask the person, “Do most people tip you for this?” Depending upon their response, I can usually figure out an amount, but sometimes I’ll follow up with, “what do they usually give you?” Most people are honest.
To those responders who don’t like tipping and who feel the amount should be included in the upfront price, I would suggest that you assume a 20% tip is implied on top of the upfront price, but, from there, you can view it as an optional discount you can make use of, in case you receive horrible service. In other words, the real price you would be paying if there were no tipping is 20% higher than what you see on the menu. Using a tip to cover that instead of baking it in, gives you the opportunity to pay less than you would otherwise.