I think that the problem with using poly is that most pro shops don’t teach players the two basics of using poly that are different from using softer strings.
- Poly plays well at lower tensions and it is possible to play well with polys on most racquets at low-high forties (lbs) tension. Most players are used to playing at mid-high fifties or low sixties with multi or gut and when their stringer first suggests poly, they ask for the same tension or maybe only a 10% reduction which is still going to give them a very stiff stringbed. I bet that the majority of poly users outside of this forum have never strung poly below 50 lbs and ever experienced a comfortable string bed with poly.
- Players are used to playing with soft strings for 3-4 months or till they break. They are not advised by their stringer that poly loses its resilience and goes dead anywhere between 10-20 hours with stiffer polys getting harsh in a few hours and softer polys taking longer. Most players don’t break poly and they keep playing with it for many months or at least till the tension drops so much that control gets very erratic - this is usually many hours after it has gone dead and started transmitting many harsh vibrations to their arm. If stringers advised players to cut out the poly and restring as soon as they feel some discomfort or a ‘harsh’ feel which will definitely happen within 10-20 hours, we wouldn’t have the epidemic of elbow injuries from poly.
In general, I would agree that poly should be used mainly by players who will break it relatively soon as they are likely the ones who have the swing speed to get the ‘SnapBack’ effect that gives extra spin. But, if others want to use it due to the extra control or lesser depth it provides from its lower launch angle, it is likely ok as long as they string below 50 lbs and restring within 10-20 hours (depending on whether it is stiff or soft). But, please don’t use poly because it is ‘durable’ meaning that you never break it and use it for many months or because it doesn’t ‘move’ even after many weeks and then complain that poly strings always cause elbow problems for all older players - you are not using it right.
Also, unless you break multi/gut within 20 hours or do your own stringing, poly is probably not going to save you money if you use it right and restring every 10-20 hours. You will likely get twice the amount of hours with multi and thrice the amount of hours with gut without too much tension drop hampering performance. So, you have to compare the price of two poly string jobs against once with multi and three poly stringjobs against once with gut.
