Breezy ,it doesnt follow that because the people you booked attracted People to your club,that they would do the same somewhere else.
Quote from a long time pro, to a newbie organiser in 2001

'Keep out the traddies, they'll kill your club; really? breezy.
well, let me tell you something ,and this illustrates my earlier point,two of the worst attended nights that I organised were for two singer songwriters[one of them you mentioned],however when I booked artists performing traditional MATERIAL ,the club was packed.
its a mistake to generalise from your particular clubs experience,clubs vary tremendously all over the country,and what may be popular in st albans is not necessarily going to be popular on TEESSIDE,or in Aberdeen
I know this pro you alluded to, [he made similiar remarks to me,and he does/or rather ,did not sing traditional material, in fairness, hardly an unbiased opinion .,as far as my club went he was completely wrong,they appreciated quality trad material,just as much as they appreciated him .