I agree, use the Madan in whichever way you are comfortable and works for you. When my boys are clean and tangle free, I brush from top to bottom. When they have tangles or are a mess, I do line brushing -- small sections, starting at the bottom of the hair shaft.
We have 2 Madan brushes from Jenny and love them. Also have the large Madan comb that I steal from the boys for my own hair.
Oscar is adorable as always and you take great care of his coat.