From what I can gather, they just kinda added a gear, but split all the other ones to the point it did not really help. Low is LOW, like pull a house down low, but 1 is to high to comp for the added help by the time you get there. 2-3 is short - not enough rpm to make them happy. 3-4 is not bad, but 5 is not high enough for speed, not low enough for not having to down shift.
Some guys love them, I do not miss it one bit. In traffic it was hateful, there was no good gear to just kinda limp along with. Towing it had plenty of umf, as long as you did not mind rowing gears slowly and running them out to their fullest every time.