I realized something today while adding new shoes that others may already be using, and is so obvious I can't believe it didn't hit me earlier. Actually I can.
I use two runscribes and my left / right numbers are different. A worn pair of shoes validate it.
It struck me today that I could create a Left & Right shoe and assign it to the corresponding run scribe, L/R in the portal after a run is uploaded.
Currently when I look at stats for a shoe, I assume that it is an average of L & R.
This approach should give accurate stats, by shoe, by side and is something I haven't seen on any other platform.