In BJA2 it states that Don's betting scheme for double deck tops out at 6 units at +5 true as an example.

Assuming you were playing a DD game in which cover was not needed and heat was minimal, ideally would one spread to two hands similar to what the book says to do on 6 deck games ie: 6 units one hand at +4 true and spread to 2 hands of 6 units at +5? Or would you spread to two hands on DD say at +2 instead?

I am trying to maximize profits but still keep my ROR equal or better than playing one hand.