I was screwing around last year with high tension ALU Power in very soft PT57A frames. Got up to 70lbs I think. All was great! Then one day, my elbow literally started taking on fluid as I drove home from the club. I promptly switched to a full bed of gut and took a week off. All was well. Went back to gut/poly for the rest of summer, fall, first of winter. This spring I had two genius ideas - one to revisit full poly but at 54lbs and/or 52lbs, the other was to try poly mains/gut crosses. I also decided to try a larger grip at the same time ( I have big hands but play with a 4 3/8, went to 4 1/2). First match with full poly I was returning a big serve, locked up my forearm and insta pain. This was actually worse than the previous summer, in fact, previous summer didn't really hurt, just fluid on the joint. Pain was in my upper forearm halfway between my elbow and wrist. Took a week off, switched back to my gut/poly, no issues. Then decided a few weeks later to try that poly/gut frame. Played two low paced matches with some older friends, pain was so bad I couldn't finish the last set of the last match. That was a week ago. This time it was so bad I couldn't make a fist, open a jelly jar, etc. without significant pain. Iced it, started taking some prescription NSAID, today all feels fine. What I have noticed, I can find the insertion point of the tendon and on my injured arm it is noticeably swollen. Not like a huge lump but certainly more larger than the other arm. I think I am going to hit tomorrow with my full gut frame strung at 60lbs. Might restring another at 56lbs. A friend of mine who has been playing for 25 years longer than me is of the opinion, once you get it from messing with poly, its best to avoid poly for years, if not forever.