I have seen the overpainted textured thing before and had to restore some of it - it was definitely thick gum arabic over dried watercolour

Whether this one is watercolour I don't know (don't think so, at least not in some parts), but I think it's a similar technique of adding a clear medium over the paint. It's only really in the bits where more depth is needed (dark folds of the coat etc.).
The checks on the leg could be explained by the colour being a wash over the original photo...
Bruce, if it ever gets taken to a conservator, I'd love you to tell us what they determine it is

We can speculate until the cows come home (and probably will)

Cheers
Prue