Quote - There's a bevel option in the W key menu, but that will bevel all the edges in the model.  There is a python script that will bevel just the edges you have selected (Scripts->Mesh->Bevel Center).  It can do some strange things sometimes that require manual tweaking, but should be fine for what you're doing.

Thanks for that, HaloedRain... I tried it. I think I don't understand the parameters of bevel, as it essentially blew up... distorted the entire mesh beyond recognition: turned it into an asteroid.

Suppose I should preface with what my intentions are: what I'm trying to do is make clothing seams look like clothing seams, and clothing folds and wrinkles look natural. Somewhere along the line - perhaps during the Poser smoothing process - the carefully manipulated geometry ends up looking lumpy and weird. I know that it can be done - other modelers have managed: just look at that wonderful free example by As Shanim... "MyShirt" - and I certainly can't imagine or accept that Blender wouldn't be able to do something so rudimentary.

The strategy I've chosen at this point is to make a loop cut (using [K] ) just adjacent (as in, on either side of) the geometry that makes up the clothing seam... so:

...which gives Poser a bit more mesh to chew on. I hate adding geometry - especially since my mesh is fairly high as it is... in this case, 10,568 verts - but I don't see an alternative. Here's what I get:

I consider that a relatively satisfactory-looking seam. However, it's not just about seams... if I want to add folds and wrinkles in clothing, Poser's smoothing makes them look more like lumps than folds, as you can see. I'll try some additional strategies that will hopefully not end up placing tris on my mesh. I'll let you know how I go.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

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