Hello!
You are right ...the discussion whether OS .40X or TT .40SE is the most powerful engine is totally meaningless because these sportengines have nearly identical poweroutput and there is more up to the individual user which is more powerfull!!
And you are also right about that excess power can put you in more trouble than you ask for!
Building light and put on as light engines as possible is the rule of thumb in both sport and scale models...or should be......
I have been and is ...a pylonracing guy and in pylon we have a lot of power! and the engines are not OS and TT.....

Regards!
Jan K
Sweden