Quite right Danny, 55 kts was appropriate for the Tiger Moth, but they would cruise at 90 mph/2050 rpm. My pilot side wanted to crack on, the grease-monkey on my shoulder whispered "1930 design and casting, white metal bearings, Avgas 15p a litre" so I throttled back to 1850 rpm and about 75 kts. After all I had to pay for the Avgas which gurgled down its gravity feed much more quickly at such high speeds
The Jackaroo's fine pitch prop lifted the load but restricted cruise to 70/seventy mph. The Gipsy Major was very reliable but I never pushed it not least because the repair bill would fall on myself and not Her Majesty, assuming I was able to walk out from the pieces. Not that I minded, for Their Majesties often required the ultimate price for your generation's aviation.
Another memory of Tubby Dash my instructor. Relatively little has been written by WW2 instructors, Yellow Belly (Chance) being the only book I have encountered. Perhaps this is because so many operational pilots were posted to instruct as a "rest". I could not get Tubby to talk about his wartime experiences except on yet another rainy day to delay my first cross-country. "Listen, son, better down here wishing you were up there than up there praying you were down here".
I asked him what he remembered best about a lifetime of instruction and he gazed out the rain-lashed window for at least 30 seconds. "Seeing young men grow up", he replied. When at long last I found myself alone in the skies for the first time, I began to understand what he meant.