Thank you all very much for your help. The query has been all about range speeds and attiude, mostly starting with "how can it be true that.." and I didn't even know if it was true. During the exchanges my interrogator produced a 172 graph (
www.pplkonyv.hu/download/C172-Penaud.jpg) which, as I said earlier, confirms Vmp at 60kt, Vmd at 75kt with a high nose attitude and recommended cruise at 95-105kt. He also produced another diagram from (cough) a well known school that said that Vy was Vmd.
I think we have sorted this out, but thanks again
Dick