Is this a bike fit issue or physiological?
 

I have noticed that over a period of time, my bib shorts start to wear out at the point of contact between my right sit bone and the saddle. This probably indicates imbalance between the two legs. I don't have power meters to verify that.
So, I am looking to seek the wisdom of the general populace to figure out what's the best way to diagnose this and then how to resolve this. Growing up, I always had issues with my knees where they would buckle under sudden pressure from change of direction or sudden stoppages. So, I may be favoring my left knee unconsciously?
Incidentally, this happens only on Rapha shorts. I have a Specialized pair that outdates the Rapha ones but it shows no such signs.
Thanks!

A lot more people than one would think have mild scoliosis. I have trouble with saddle sores on only one side. I've had my legs measured by a doc and they're the same length. So that's my guess. A good doctor can tell by examining your back muscles for asymmetry, no X-ray necessary.

Jeez, how did we ever fit ourselves before power meters? Maybe your saddle is crooked, bent, or too high, maybe your hip alignment is crooked, maybe one leg is shorter than the other, maybe your cleat alignment is off, or maybe your pedaling dynamics are just asymmetrical. Sorry I can't fix your problem, but hopefully I've given you a few things you and a riding buddy or professional fitter can look at.

Have you examined the shorts to rule them out? The difference between the two seems like the biggest clue.

Thanks! Now that you mention it, I did see a chiropractor once who said something about my lower curvature. This was years ago though. I'll try to get my records from them and see what exactly it was.

This is exactly what I was hoping for, that is, the things that I can cross off and the things I can look further into.

It happened on 2 Rapha shorts. Maybe their material is softer and hence wears out more than the one on Specialized shorts.

Unless you have 12 pairs of Rapha and 12 pairs of Specialized shorts, each showing the differences you claim, then I wouldn't put much into your hypothesis other than it needs more investigation.

As do I. And I'm trying to solve a right sit bone area pain problem. It may be sciatica, but maybe has something to do with my scoliosis.

See the bit about walking in this post: https://www.bikeforums.net/22781075-post103.html
When I had sciatica, my lower back hurt like the devil for the first mile, then it was fine. I walked every day for a couple weeks, went away, did not return. My saddle sore OTOH is still around, but it's just a flesh wound..

Another possible issue is saddle is too narrow and you are pushing harder with your dominant (right) leg and moving slightly off the saddle wearing out the shorts on that side?