How would triple click add an extra delay to a single click? Wouldn't it only check for a third click using the same delay AFTER the second click only?
That would be too logical. I did not enable triple click, so I have no idea. The double click delay never troubled me. I never even noticed it until it's mentioned here.
Seeing that double click needs to be detected, one thing Apple could do was to let the user shorten the delay in the configuration, and perhaps detect missed double clicks and increase the delay after a certain number of misses, or reduce them after a number of hits as the OS can tell how fast a user can double clicks.