Interesting thought --
I'm a GA pilot and all my RTF training has been in the direction of trying to eliminate unneccessary words, including a brief 'thanks for the...(whatever).'
It doesn't seem quite right to me, however, and if traffic is quiet, then I 'll usually express my appreciation for helpful or smooth handling.
By the way, its not because (in a C172) I don't pay airways charges, since I more than make up for these by the duty on Avgas .
Also I should think that a 120kt a/c in a 250kt environment causes its own fair share of problems for the poor ATCO, especially in the TMAs.
Anybody wat to shoot me down??
Regards