Some [sessions] are visited by very skilled players who are looking for a particular 'fix' - and, as I've explained, they can't get this in a private gathering - so tune sessions really do need to take place in public.

I understand exactly what you mean here, Tom, but I think there's a fine line between the need for a fix and the need for an ego trip on the part of some players. Speed for its own sake (for example) is one of the symptoms of the latter.

I think that the best tune players I've ever met are those who are willing to accommodate newer, less experienced players and to encourage them to take part - even to guide them and show them where things could be better. I think the continuation of the music does depend on tunes being handed on. (Perhaps "handed on" is not the best phrase - "brought to attention" might be a better one). If we make this process difficult or unpleasant, then there'll be groups of ageing skeletons sawing away in corners in the future... :-)

And, yes, inexperienced players should keep their ears open and practice hard so that they and everyone else will enjoy the communal experience of music making.