I've been studying my mechanical TB to see if there is a way
to keep the advantage of the groove while the engine is at idle
in order to make my engine more "hybrid-like".
I'm not getting the advantage of having the groove while
the engine is idling if no air is passing thru the groove because the TB is completely
closed.
I would like to bypass the idle-air controller (which is a TB bypass system itself!)
I've been looking at the mounting bracket for the throttle cables to see if
I can attach something adjustable there to hold the TB valve slightly open
at idle. If this works, then I can go ahead and block-off the idle air port
but still leave its electrical connector in place to hopefully avoid throwing
an engine code. Any other ideas about this out there?? thanks.

I don`t know why you would want to do that but cable drive it can be done. Just groove throttle body exactly at the butterfly the edge will allow enough air to idle.I don`t think its worth the extra work for no more gain than you`ll get.But good luck and keep us posted.

Great idea Dan, except that I don't have any bits
or Dremel tool (I'm not a personal license holder yet)
and more importantly I wanted something that was easily reversable.