More oil in the fuel will not reduce the static power but wont let the engine unload as well once in the air. There is a certain amount of oil needed in the fuel for the glow airplane R/C engines to give the maximum performance and last and that is something between 15-20%. Too much oil and you will lost instant throttle response, midrange reliability and unloading qualities in the air. Too little oil and you will lost torque and idle reliability because our glow engines run a little bit like an diesel engine and will lost compression with less oil in the fuel and simply run too cold. Thats one reason why good old thick castor oil is such an great additive for syntetic fuels. If one must connect the crankcase nipple to the carb it should be connected to the carb body cone "inlet" where it sucks air and fuel and before the throttle drum. The OS200FS has done it the wright way. Connecting to the intake manifold is not good as there are pulses going forth and back and the oil drops are just in the way.