Bert- Yeah, the "A" is infinitely milder than FK1119, which even softened up old laneline paint well enough for me to just peel it off.
Just FWIW, I always use a solvent if removing tar the chemical way (I usually just clay it off with Sonus SFX). AI/VG`s New Car Prep might be a better choice for tar removal.
AFAIK, the ABC is really..or at least was originally...developed as a New Car Prep system. We use it for across-the-board Decontamination, but maybe that stretches things a bit thin.
I suspect that the whole "first, do no harm" (especially to a manufacturer`s New Vehicle Inventory) is kinda taking priority.