Depends what soul event it is I suppose Ian.
I've been playing a right mixture for a good while now and I find it works better for me and for getting a crowd to accept what you are doing.
I have just re-done my poster for one night in particular - it had 'NORTHERN SOUL FUNK LATIN SIXTIES RARE GROOVE' on it, giving me the option to play across the board - or so I thought - I've found increasingly that over the last few months that if you put 'NORTHERN SOUL' on your advertising, even though it is amongst a group of other styles, you get groups of Soulies turning up moaning every time you play anything else other than Northern.
No other group of black music lovers who attend do.
My poster is now void of any genre, just stating 'THE FUNK SOUL BROTHER', make your own mind up what I play.
Of course there is a place for stuff like that....keeps it fresh.