Despite my total ignorance of what goes on in folk clubs in England, I'm finding most of this discussion quite interesting, and have another couple of cents' worth to offer:

My immediate reaction to a so-called "purist" is to allow that everyone is entitled to his/her own opinion ~ each to his own taste, so to speak.

However: there is one particular strain of trad orthodoxy that I find obnoxious and essentially anti-musical. I refer to those who insist upon blindly aping, note for note, a particular early-twentieth-century recording. There's a lot of this going on among traditional-jazz enthusiasts and some (but thankfully not many) folk-blues players, and I suspect that the "just-like-Bill" bluegrassers that Martin was complaining about are up to the same ignorant nonsense.

Don't these people realize that the recordings they so slavishly imitate represent nothing more than the way their idols played a particular number ONCE, on the day they happened to be recorded?

Early jazz, especially, was nothing if not spontaneous ~ group improvisation ~ but some of these worshipful "recreators" treat a given recording as if each note were engraved in stone. I have the same complaint about acoustic-blues performers who drop a beat from the same measure of the same verse every time they sing a particular song because that's the way Blind So-and-so sang it one afternoon in the 1920s when someone dropped by with recording equipment.

I would hope that those traditionalists who are devoted to *older* forms that predate the emergence of recording technology avoid falling into this trap, but I'm willing to bet that there are some who cling desperately to the earliest *recorded* versions of their favorites, despite the fact that they are attaching themselves to early-20th-century versions of songs from the 19th, 18th, and earlier centuries.

OK ~ rant over...