Nicely put les.

I play penny/tin whistle mostly for my own amusement and occasionally at music/singarounds depending on how confident (or sadistic) i'm feeling. One thing i have not done yet and thinks i would find very difficult is joining in a session. I really admire those sessioners who seem to just pick up a tune with others as tho they're on a kind of 'mind blend' - as you would see/hear if you visit the Jolly Angler on a Sat night. I suppose practice and familiarity is the key with a dash of technical skill of course.