By "well in advance" I meant merely 1/2 to 1 second. Enough time that the ProntoEdit software pops up its dialog saying "Waiting to Learn" before making the move to press the button on the originating remote.

But having learned 20 previous devices as mentioned in the first post, I wouldn't have thought this to be an issue. Making sure the batteries are fresh in both units is always a really good idea.

I've put my TSU2000 through a pretty rigorous duty cycle for learning and I've never seen this issue with any NEC signals following a 4-5" guideline and letting the software get up to speed before sending the signal.

Bruno