I seem to remember that when the ESDSS looked into the way that PRS returns were calculated they found that only the two largest venue classes were taken into account. The returns from the smaller venues were all binned - which effectively ruled out any income for folk performers. The returns from these smaller venues were merely apportioned in line with the large venues. This would mean that you could put a return in for a Harvey Andrews number, but the money would go to Paul McCartney etc.