He's after friction though so cable pull wouldn't matter, surely? I agree that its best to just swap it and get the right tool, but failing that: is it possible to remove the ratchet or anything I wonder?
Shimano friction feel like crap, hence the recommendation of dia compe (or wait gran compe?).
Those friction have a much lighter feel, and feel more precise, the only problem is that the shimano derailleur tend to have a slight lags in feedback.
Just so you know, cable pull on 11 sPeed is different to 8/9/10 so can't work.
Best return it and either get proper friction (dis compe make good one) or get shimano dura ace 9 speed bar end or downtube.