Let me first say that I think the practice of tipping is out of control. What used to be 10-15% of pre-tax pricing has become servers expecting to be tipped 20-25% of the total bill, regardless of the service they provide.

But there's still a strange line of thought in this thread. Do people really feel they're tipping a server for carrying a plate of food from the kitchen to the table? Are they tipping for things like how fast the food comes, etc? IMO, those are the wrong things to base a tip on. A server, even in a low-end restaurant, is a kind of guide to your dining experience. Their job is to make sure you're having a good experience. That includes greeting you, explaining the menu (if necessary) and any specials, offering suggestions, checking in to make sure things are good and you have what you need, etc. They need to understand the menu so they can answer any questions customers have about preparation or ingredients. It's also their responsibility to make sure your order is accurate, as it goes into and comes out of the kitchen.

It's not about plopping a plate of pasta or a steak down in front of you. I'm pretty sure the restaurant industry could train monkeys to do that -- and they work for bananas. Tip based on the experience, not for simply receiving your food. And I'm still in the camp that adequate service receives 15%. Poor service receives less, and excellent service receives more. I'm sure a lot of people disagree with those numbers, and that's ok with me.