So many posts about tennis elbow. ..Well, here' my $.02. I've had surgery on both elbows for TE so I know a thing or two about it. In my view, it is NOT that one uses poly strings, a stiff or light racquet, or even a slight change in form, it's HOW ABRUPTLY one changes one of these variables. Wanting badly to avoid any additional problems with TE, I've applied the same approach I use in incorporating new exercises to my workouts to changing strings/ racquets, etc. In short, I make changes GRADUALLY and therefore leverage my body's ability to adapt. Sensing I might prefer the playability of poly strings, I strung just one of my three racquets (Volkl MP10) with poly. ..I started out hitting with it for just 1-2 minutes. ..The next day my arm hurt a bit. ..So I waited until pain was completely gone. ..Then, I stuck to using it just 1-2 minutes at a time UNTIL I didn't feel any pain the next day. This took several weeks. I then gradually increased the amount of time I spent with it until I reached a point where I used the poly-strung racquet exclusively. Later, believing I might play better with a stiffer frame, I went through a similar process with racquets. I took just ONE demo out at a time, then used it for just a few minutes before putting it away. Eventually, I decided the best frame for my play was the Wilson BLX Blade 98 - a fairly stiff frame known to be a bit harsh on the arm. ..I bought one, then VERY GRADUALLY increased my playing time with it. …And now, I'm able to use it exclusively - w/ poly strings - and it has improved my play. Another bit of advice: Be careful when taking lessons… During a match one might hit 10-12 backhand volleys… But if you take a lesson or do a drill-clinic, you might find yourself hitting 40-50. Again..an abrupt change in work load that may lead to or aggregate TE. This very thing happened to a 4.5 rated friend w/ excellent form. ..He was convinced his racquet/string setup was to blame without ever considering how he abruptly increased the work load placed on his elbow during that one drill clinic. So, in my view, poly strings, stiffer racquets, longer racquets, increased volume of backhand volleys, etc… are all possible provided one incorporates these changes very very gradually. Our bodies are wired to adapt to new/ heavier workloads so longs as you give ample time to do so.