Interesting... checking the safety codes as listed on the NAR website, it appears that there is no such stipulation in the "Model Rocket Safety Code", but there is in the "High Power Rocket Safety Code":
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- Weight and Power Limits. My rocket will weigh no more than the motor manufacturer's recommended maximum liftoff weight for the motors used, or I will use motors recommended by the manufacturer of the rocket kit.
-------------------------------------------------------------------------- The irony here is that manufacturers of "high power" motors generally don't provided recommended weight limits like they do for the "model" size motors... so the net effect of this would be to give "force of safety code" to the specific motor types recommended by a kit manufacturer. (That gets tricky for stuff like LOC kits, where the instruction cards seem to mainly list obsolete motor types no longer avaialble...)
-dave w