I used to think that but during the Yonex Denmark Open Taufik Hidayat vs Viktor Axelsen Taufik during the 2nd game switched from the Arcsaber Z-Slash TH to the Arcsaber 10. If I get to mop during the olympics I want to get his racket.
We know there was a photo taken of three arc-z-th rackets at HKO and that they should be stringed 19-24 lbs
Haha I know of at least two players who are not exactly of Taufik's stature that string it at 35lbs ... As for the low recommendation perhaps the answer is in the explanation of the "SG" symbol (on JP rackets and well you know you can't go around allowing higher tensions on non-JP coded, what will the people think ). In the bit I posted it was mentioned products that pass the test and receive the SG mark are entitled to cover their warranties from some general fund by the SG foundation. Mizuno's don't exactly have a high max recommended tension afaik and also carry the "SG" mark and perhaps we could deduct from this that these are the tensions at which they still qualify for the coveted SG mark (japanese consumer perception +, warranty covered by someone else + ).