Before I had subcision, when I pulled from two directions like that my scar totally disappeared like yours. During my subcision my doctor mentioned that my scar were very tough with a lot of tethering. So I think there are tethers in this case.

I have scars exactly like yours. They look like boxscars, but they disappear if I pull the skin with my fingers, as if there was a little atrophy under those little scars. All that remains is to try the subcision, and see the eventual improvement.