Where on earth do I put 3 batteries going up Mam Tor..( and no not there).
Posted it before but couple of weeks ago cycled up Pico Neulous, represented a vertical climb of 3800 ft.. Average speed 7.2 mph, Time to top 1hr 50..On a single 400wh battery..All off road,over shingle, rocks, boulders and nud....
Yes it represents battery empty ( it had 3% left) but at 4000 ft you have enough potential energy stored to cycle 40 miles unaided...
Flecc
I still think you are missing point about gearing. Yes in an ordinary road bike, with road tyres with plenty of pressure in them and bice smooth roads yes 2 speeds for emotor might be fine..
Throw in rock strewn paths, with bike running 2.5 inch tyres on 25 psi ( I,d go less if I could fit security bolts like on trials bike) or even 4 inch tyres as is getting popular now,, plus 2 inch deep mud, occasions 1 in 3 hill ( still covered as above) and motor to provide any real help ( especially if its only 250w) needs lowest gearing possible.
We are just not comparing like with like. Yes , hubs are probably fine climbers, my Mondeo is on the road..Xant compete with oldest land rover in world, even I it could get traction.
Simple thing is the crank drive has the adaptability to do both jobs. Perhaps on road climbs ( perhaps) the hub is superior. Off road crank every time.