I missed this post amidst all the jokey fun stuff, clearly.
Whenever I arrange a meet, be it mf, mmf or mmmf, I certainly don't have any expectations of guaranteed performance either on my part or that of my partner(s). I find it helps to relax and not expect anything - I certainly wouldn't judge anyone who couldn't get hard. There are times I can't orgasm, no matter how I am enjoying myself - that is no reflection on my partner at the time.
It happens, that's all.