I've no problems with anyone riding a fixed wheel. The only thing from the CTT rules to note is 'Bicycles with a fixed wheel shall have a left hand threaded locking device securing the fixed sprocket' Please don't ask me to explain that one - no idea what it means!
Does this raise the issue of whether there should be a scrutineer to ensure bikes comply with regs in order for event to be valid under CTT rules.
Is this a can of worms where someone could ask 'If I fall off and no-one checked my bike complied with the regs can I claim against organiser/club etc?'
To address Cath's comment, this seems to be referring to a lock nut to secure the sprocket. It's a 10 second job to see if there's one there (if, referring to Dr Dave's comment, such a check is indeed required).
Well my lockring is in place so all is well. Looking forward to giving it a go now. Don't worry Cath, if my sprocket spontaneously unscrews itself I won't hold you responsible!
No one is going to be checking anybody's bike - if someone's wheels fall out and they fall off cos they forgot to put the quick releases in - thats their problem!