That Would Be The "Activated" Oxygen Bleach of the T
IIRC it was some sort of maganese (sp?) based chemical and yes, it did a number on many a poor wash load. Product was quickly pulled off the shelves and now the only two oxgyen bleach activators in common use are NBOS and TAED.
P&G owns several patents for NBOS based oxgyen bleaching systems, which is why you only see it on their brands such as Tide, Gain and Cheer "with bleach".
TAED bleaching systems are used by both Henkel, Unilever, and IIRC P&G amoung others all over Europe. IIRC, the reason for this is that TAED is better suited to soils and stains found on that side of the pond, and the longer wash cycles with hot or boiling water.
NBOS bleaching systems are better suited to the dilute (read top loading washing machines)water conditions, as well as "tap" hot or "warm" water. Indeed while both TAED and NBOS actived bleaching systems are designed to work in "warm" or even cool water, the later has a lower threshold that is will work at <104F. Again given American top loading washing machines did not nor do have built in heaters, the water temp is always going to be a mix of several factors, none of which are accurate.