i know this an old thread but i'm currently studying this topic and stumbled across it.My understanding of the subjest is when increasing power you advance the rpm lever first then the throttle for the following reasons, the advancing of the RPM lever will reduce manifold pressure, then opening the throttle will increase it again this keeps the manifold pressure down, if you advance the throttle first you are increasing the manifold pressure straight away and this could exceed the critical pressure of the mixture leading to detonation. Likewise when decreasing power it is advisable to close the throttle first(decreasing manifold pressure) then retard rpm (increasing manifold pressure) otherwise you are again running the risk of increasing manifold pressure to much in the first instance resulting in possible detonation.If i am way off the mark please help me out as I am pretty confident i have this understood(maybe misguided confidence i admit)but some posts on this thread point to this as poor information.