Thanks for the comments,

the pain was first noticed on a training ride, 60+ miles, insidious onset, and only evident when seated and pushing a high gear, i.e. demanding effort ++ on downstroke, and eases as soon as effort is reduced,
following initiation of pain, pt. is left with a feeling of 'weakness' in adductors (though when tested, none evident) although lat. rotn. m/strength may be slightly reduced.

palpn reveals deep adhesions to piriformis and surrounding tissues, which have reduced with rx.

I have tried deep sstm and piriformis stretches which seem to have relieved symptoms to a degree and have introduced theraband exercises to address rotator weakness.
I think part of the pt.s problem may be psychological ? imagined rather than real injury perhaps ?

thanks for all your advice, any more much appreciated.