Keep her above 4000rpm and she'll thank you for it every day.

[Brucelee]

Stress leads to fatigue, wear comes from friction, these are two totally different mechanisms.

Are you suggesting that stress does not lead to wear? If I incease the stress on a bearing are you suggesting that it does not wear faster than if I lower the stress? Are you suggesting that engines that are supposed to run at very high piston speeds don't need to be engineered to handle the stress?

Are you suggesting that if I run my Boxster at 6K rpm, that concussion, heat, friction, and mechanical stress are not all higher than if I run it at 3K RPM? What about the impact of higher temps on metal fatigue?

I can't see any way out of this for you. Explain how all the factors that contribute to metal stress and wear are not higher at higher piston speeds and higher RPMs.