Seems fine to me. The 'optimal range' though is based on elasticity of the spoke and providing cushion against unloaded spokes from becoming detensioned and seeing higher fatigue cycles and/or loosening over time due to de-tensioning. I believe Zipp accepts some tradeoff in longevity for ultimate race performance though truly knowing how close they are to an actual failure limit is tough, since it is presumed that Sapim's own limits have engineeing tolerance as well.