I am not "lecturing" You Dick - you're an old dog like myself and we don't want to change... but I feel we are both being "lectured" by many of the even older dogs barking in those old tutors how things shall be done."Not having encountered any problems" often means that we have gradually formed ourselves more or less unconsciously to circumstances which are not perfect - in the end to the degree that we believe that's the way it is, or even that's the way it has to be.In the end someone always believes that's the only way that is "right" and starts a mission with that cause...
I'm afraid the guys you mention are pretty close to most of us in the sense not being prepared to change since it takes too much effort to reconsider.There are several details that might be reformed with the concertinas, not only the english of course, and it is not difficult at all to realise that not only comfort but actual performance capacities might be much improved. BUT like I have said many times before - it IS highly dependent on individual conditions WHAT improvements are possible and WHEN they may be of particular significance.Many excellent performers obviously do things in an way that suits THEM and naturally have no interest in a 'new' concept neither for the instrument itself nor method of playing - if they have a "winning concept" of their own.But development may also come natural and you MAY get fed up doing things the 'good old way'..:-)