Gentlemen...theres been some very thoughtful and useful comments on the do's and don'ts of using right thrust...(note : for a clockwise rotating prop).....Looking at "P" factor on a 3-dimensional axis....Prop slipstream ...upside blade angle of attack vs downside blade angle of attack....its all good info to use....The question that really counts that I ask is what do I want to accomplish?.....The answer is different for each of us depending on application...I fly Giant Scale warbirds and thru experimentation have found that right thrust doesnt make enough difference to require its usage.....What I have found is during takeoff if the throttle is applied quickly much more rudder is required to maintain runway heading vs applying throttle gradually...but once airborne and after trimming the warbirds fly very straight and true.....on an occasional loop or stall-turn moderate use of rt rudder keeps the nose on upline easily....also makes cowlings much easier to install......but I can see where thrust angle offset makes sense on Aerobatic or Pattern type airplanes.....its more a matter of what application is used and personal choice.....either way works....just my .02 cents worth.....Bill