Ok, I feel you must have misinterpreted the instructions in the manual.
After the initial screw setting (1-3/4 turns) and warm up you should individually turn a screw out. (1/2 turn) if no increase in rpms is detected turn it back in to the base setting. Do this separately for each screw (carburetor).
If an increase in rpms is detected when you turn a screw out 1/2 turn, then turn that screw out again 1/2 turn. If no increase of rpms is detected then, turn that screw back in 1/2 turn.
What you had done is had every carburetor running too richly initially on with all the blanket turning out of the screws. Remember the base line is 1-3/4 turns out from lightly seated. When you are attempting to adjust a single carburetor all the other carburetors should either be at (1) the base line setting, or (2) the final adjusted setting.
I hope this helps you to understand.
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That does help. I was scratching my head over this, but read and re-read a post very recently that came to the conclusion it is done collectively, which made no sense. THIS I can embrace.
Thanks SO much for the wisdom.
Guess there's no need to take the battery out of the DigiSync quite yet...