stem shifters
Ive been thinking about the same problem. I've just bought a Condor touring bike with indexed 6-speed rear and friction front derailleur levers on the down tube.
Not sure whether to a) get used to them (I wobble horribly and it's a stretch to them - I've fitted a stem raiser), b) change to stem mounted shifter (a Shimano TY20 from SJS?), or c) a band-on shifter on the top tube.
I've never seen the latter, but it would solve the problem of having to use cables from the down tube stops. Would it matter having the bare cables going up parallel to the steerer tube, but a couple inches behind it? Also I likely to be able to get away with just buying band-on cable stops, and swapping the stops for the gear levers? (will the threads be compatible?). I guess another solution is to put old "thumbies" on the drops - will they fit? Ideally I want to get away with minimum refitting of stems, handlebar tape etc.