You’re still missing the point that the key valuation question (as noted in #msg-77401502) is how long a given company can continue growing at the mid-sized annual rate you specified. Your statement that your own investment horizon is 10 years is immaterial to the question at hand.
My comment and your answer address two different "valuations".
If future growth rates and future discount rates change; and/or you want a greater return (that bogey could easily replace the discount rate) then the PE is still calculable (provided the GR<DR, or the GR is for a limited period) - but the PE you would pay to achieve your hurdle rate is much lower.
I just did not understand your statement. Now I do.
Market Data 
Markets 
AI
