Dick:"Guran,I find it marginally easier to get more emphasis when pushing.but [imo]the important point is the reversal"

RE: Well, for the bodywork itself it hardly matters whether the emphasis is on pull or push, the antagonist muscles usually are just about as strong,but habituation is important and one can not just change any habit and be comfortable with something new. Simple mechanics however ought to tell us that having the emphasis on pull is more efficient, it is just a matter of being consequent taking the time to re-learn ( if one wishes to sacrifice the necessary agony from the crossover phase of course...)

Never mind, I do agree that finding musically natural and expressful methods is the main object!If we compare fiddle and concertina again it also comes more analogous having the emphasis of the strong beat
on "down-bow" and "pull" respectively as the arm movements then will be more alike: drawing the arm outwards.

If you haven't tried it before DO try just for curiosity the "cross-the-bellows-strap" trick I have advocated for since many years. It is entirely un-orthodox and many players may find it "cheating", or even silly, but there are a couple of proficient players who have adopted it (after some initial hesitation...)and it can mean a great deal for facilitation of bellowsing, particularly of the delcicate and quick reversals we are talking about here.