I think a term is being misapplied. ATF has 'friction modifiers' in them, not 'friction enhancers'. This means the oil is compounded to react in a predicable manner in the friction area between clutches and plates (?). I don't know the chemistry of the additives, but it certainly could mean they allow extra slip as opposed to less slip.
Oil stock destined to become ATF is one of the highest cuts of base there is. When you combine this with the high performance additives, you end up with a 'super oil'. The modern automatic transmission is the most hostile environment on the whole car. It has friction and heat, ball bearings, bushings and sliding valves. One oil has to accommodate all these concerns.
I can't imagine that anything is put into this oil to increase friction, but I'm not a fuel and lube engineer.
Stuart
