Bill, my curiousity is mainly without any USB attached (no host computer).
I think Jim' experiment has confirmed my impression that the UNO (R3) cirucuitry is causing the "no-wait" to actually "wait".
Thanks, Jim for the experimentation.
I think that was a clever trial and quite helpful. Again, it's just a curiousity. Not a problem.
I wonder if the Optiboot gurus are curious too.
Cheers to all who contributed to this discussion!
TheGipp