Commanche 250:
I just can't let this pass......
You say:
" Ah right so, its okay to overboost your engines but its not okay to have them running at 50rpm more than would otherwise be, set at cruise power on a 2 mile final! How silly of me not to realise. Its six of one and half a dozen of the other. "
I don't know what you are flying, but I have never seen an airplane where the RPM change from cruise RPM the full fine pitch RPM is only a change of 50 RPM with an increase of manifold pressure sufficient to produce positive thrust.
If you can't figure out how to move your prop leavers and your power levers to produce the necessary go around power before you crash your airplane I can't help you here on Pprune.
Anyhow you and I are both correct about one thing, you can fly your airplane any way you want.