Average is 10 for good shave (2.5 passes), 5 for a quick one (still 2.5 passes). About 5 years of everyday straight use.
I watched XMan's one handed shave vid about 100 times in the beginning. then practiced with a dull razor while on the couch watching movies. Then practised shaving while not looking in the mirror. Then practised without a mirror. Then in the hills of Japan, the countryside of Europe, and various other non exotic locations, including, but not limited to toilets, kitchens...
Just want to do a few in the outback, the jungles of South America and the open plains in the US.