That is not necessarily the case. There are 10s of 1000s of axonal muscle connections that need to reform and each one has its own recovery.
I studied these nerve regeneration results more than 15 years ago, and the situation was not well understood.
What I recall is that the nerve conduction requirement is significantly less than 100% for near complete functional recovery.
I dont know how to correlate # of axon connections to nerve conduction.
Again functional recovery is measured by the ability of the muscle to provide how much force how many times - like lifting weights.
It is much easier to measure his 40 time, cone, shuttle, squat and other typical athletic scores, which in the end is what matters.