One thing to remember is that while many whisk feel backwards, a back whisk is characterized not be retrograde travel, but by the man's first step being backwards. In contrast, most fallaway entrances have the man stepping forwards and leading a reverse turn to fallaway. I suppose you could step backwards as in a back whisk an continue in fallaway... is that what you mean by a "reverse fallaway" - that it's the opposite of a "fallaway reverse" (the usual step forward and reverse turn to fallaway)?
"From a very slow Back Whisk, instead of the old usuall a Wing. The lady simpy came around to be square with the man, very small steps."
That sounds like a cross hesitation?