I don't disagree, and sometimes the multiple-step-back-and-forth can be somewhat cumbersome. If I'm in a hurry and the server hasn't yet brought the bill, I'll often flag him or her down and hand my credit card, saying something like, "I've gotta run soon, can I just give this to you?" That way, once they come back with my bill and credit card receipt, I can just sign it and rush out of there instead of waiting (sometimes not an insignificant amount of time) for them to first bring the bill and then pick it back up with my card and bring it back for me to sign.

That's why I have a hard time seeing a tip as something about self-importance. If my tip were done for an ego boost, I'd want the employee to see the tip before I left (egos like to be fed, right?). For me, a tip is an honest gesture of appreciation, and when I leave a big (20%+) tip, I actually enjoy knowing that I'm giving a server a "warm fuzzy" without expecting them to respond in any way to me.

It's similar to doing something unexpected in secret like sponsoring an upgrade for a soldier coming home for Christmas, when upgrade instruments are nearing expiration--back in the days of paper upgrade certificates on Alaska Airlines, many of us in the Alaska Airlines forum would make it a regular practice to head out to the airport at the end of the year, find a gate with a soldier sitting waiting to board a plane, and go up to the gate agent, hand over the paper upgrade coupon, and tell them to surprise the soldier with an upgrade from an appreciative citizen. Part of the fun and magic is not expecting a response from the recipient of any sort.