Yes that's what makes goose biots interesting for bodies although I was surprised how strong the contrast was. I suspect the outer edge took more of the brown dye than the inside. It's amazing how magnification can point out a lot of flaws. My original photo is considerably larger (16.7MP). I can see where the excess Gloss Coat snuck out between the wrappings. I am a right-hand tier and it would also appear that this biot is from the right wing of the bird as the wraps have not laid down as neatly as they could (having been wrapped against its natural curvature).
Davie's video above shows what happens when you tie a biot in "notch up" whereas mine were intentionally tied notch down. Notch up generates a fuzzy edge that sticks up whereas notch down means the smooth back edge wraps over the fuzzy leading edge.
Here's an actual pixel shot of the body:
Note the excess varnish undercoat (sloppy) and the thread used to spilt the tails.