Has anybody tried to shift Shimano Nexus, Sachs, or Sturmey-Archer with anything besides their proper shifters? Do 7spd thumbshifters, bar-cons, stem shifters or any other kind of friction shifters give you full access to the gears? I imagine all one would have to do is measure the amount of cable on dedicated internal gear shifters and whatever friction shifter one planned to use. Still, I thought I'd ask the forum.