I have zero thrust on my Duellist engines. Had a couple engine out flights during it's short 6-flight existance. As long as there was enough air speed it flew just fine on one engine. Had a couple missed approaches on one engine and was able to go around. The fuse is rebuilt and as soon as it's warm enough to paint and fly next spring I'll get to have more fun with it.

My twin Uproar has no out thrust either and never is a problem. I'm building a twin Ringmaster and not using any thrust in that either.

From what I have experienced, as long as there is enough speed to keep the wing with the dead engine flying you shouldn't have a problem regarless of out thrust. Rudder use can be just as effective as the thrust and something you can control.