While I was looking at some of the fantastic pictures of holsters here, I noticed something. I was basically looking at the Big 3 (Heiser, Lawrence, and Myres) holster makers when I saw that Heiser and Lawrence finished their holsters somewhat differently than Myres. They don't finish the circled area, but Myres does. Granted, I didn't look at a ton of examples, but all that I looked at followed the same process.
Larry
Of course I went to my photos to check this out and I couldn't disprove your theory.
Here's an extreme example of the length Myres went to in finishing that area.