I should have said " limited success"
As far as getting the fly down what we have done is cast the fly out. Then run the boat 50-100 feet away while feeding slack into the line. The goal is to just add more line into the cast and not troll the fly. After the fly is out wait a few minutes allowing the fly to get the desired depth and then begin the retrieve.
There are also bucktail trolling techniques but I don't think that really applies here.
Has anyone tried the new faster sink lines yet?
Cheers N I