Dear Sir,
I recognize that we arrived at this four-way-stop at almost the same instant. However, you are on my right, which means you get to go first. Actually, as I read the Rules of the Road, you are required to go first. I insist. Really.
And yes, I can see that you're trying to act polite by giving me the wave. But really what you're doing is trying to cover your own ignorance of the right-of-way. That kind of thing just isn't going to fly with me.
Perhaps you didn't notice that as we approached the stop, I slowed down just an extra bit to allow you to go first without putting any strain on your conscience. I also hit the brakes just a little extra hard so you could see that I'd stopped after you. And how am I rewarded? By having you give me The Wave. Really, I'm not sure what else I could have done. Frankly, I think you should have gotten this right without any help from me.
So for the moment, I'm not going anywhere. And I'm not going to give you The Wave. You're a big boy, and you can figure it out yourself. It's the only way you'll learn.
Sincerely,
O. Handwasher
P.S. I don't think I'm a better driver than you. It's just an indisputable fact.