So, although I understand what the "B" setting does, I can't get my head around making it more difficult for the car to go forward, in order to charge the battery more. It seems like you're robbing Peter to pay Paul here.
However, I do wonder if anybody has done any real world testing to compare both options, to see which is more economical to use? Perhaps someone who does the same commute all the time, could do a direct comparison to see if one does have any benefit over the other?