Please now, let's not give the manufacturer's any more ideas with promoting new rackets. I'm no expert but my opinion would be yes, an older racket may flex a little more than a brand new one untouched. Especially if one has the tendency to flex the older racket with their hands often. To say that one needs a new racket because the current one changed stiffness so drastically, I do have a hard time believing it would happen. I think if one goes to a store and has a rack full of identical rackets, one will easily find differences in stiffness due to tolerances. Comparing a older used racket to a brand new one can also show a difference due to different batch material, tolerance, manufacturing, etc.
apologies for bringing this old thread back to life. I just want to comment that my 10 year old NS9000 XS is less stiff than most of today's mid-stiff to stiff racket (ie astrox 77, victor JS10, li ling N55iii etc) . I am not sure if back in the old days, x stiff / stiff is simply less stiff than today's, but the NS9000 XS is currently considerably less stiff than my NS9900. I also am sure that my NS900 XS is genuine.
The issue is that you have no benchmark, so you've got nothing to compare it to. You've also got no way of testing the condition of the carbon matrix, and also no benchmark for that, either.
are you saying you had the NS9000S or NS9000X? your post is not clear. i personally don't think the racquets lose shaft stiffness over time, my MP99 plays with the same stiffness as my VT80, and my NS9900 plays stiffer than my NR900
I have the NS9000X. I am not stating that it indeed lost stiffness over time. I am just stating an observation that it currently is less stiff than my Nanospeed 9900 and the rackets I have listed above. This prompts me to wonder if it did lose stiffness over time or not.