[bazza]

Graeme, it depends on what constitutes a 'setlist'.  I know a set usually means a number of pieces to be played in order at a performance - maybe  lasting an hour or so.  In the folk world it means a short sequence of tunes (say, just two or three) used for a single dance at a ceili, or for a player's contribution as part of an informal music session.  Folk players are likely to have many such short sets at their disposal - usually pairs of tunes that compliment each other stylistically. My own collection of material, for example, includes over 700 such sets - more than are memorable. To be able to refer to them in random order would be useful when practising, helpful in sparking ideas as to what to play next in a session, and as an 'aide-memoire' to remind me of sets that I'd not played for a long time.