I had always heard about 75W output on a fairly continuous basis for a fairly fit person, but wouldn't be surprised if in reality it is more like 50W when average fitness is considered and the work is stretched over 8 hours, day after day, month after month...etc. So the 25,000 hour figure not off the mark either perhaps, though I don't know enough to argue about it.

True, but also I forgot that to get the energy out of the oil you need something like a power station with all it's losses - so, maybe there's only ~17Kwh of useful energy in the oil as well as less useful energy in the man?

Arm output cranking was some 50-80 watts for myself.

Legs 400 watts. (no shoe clips)

Lance Armstrong was known to do 600 watts for 30 mins peddling.