A take-off, by definition, would involve a climb. Even if a plane was mis-rigged so as to be nose down, as soon as the nose was pulled up to take off, p-factor would become dominant. Given the relative masses involved, I don't thnk precession has been very important since the days of the rotary engines in WW-I. It was very important then! Thats part of what made the Sopwith Camel so maneuverable, though only in left turns. But that involved the whole engine and propellor assembly revolving about a stationary crankshaft. Much more relative weight than a crank and prop.