Timed practice not strengthening skills?

[northwesterly]

On my French tree, if I "Strengthen Skills," even if I get 20/20 on the timed practice, my skills don't go gold (or even make progress toward it if they're more decayed.) This happens over and over -- ace the timed practice, but no skills actually strengthened.

If, however, I actually select a specific skill on the tree and then do a timed practice on just that skill, it'll "gold up" very nicely. But that's a more laborious way of doing things.

Possible bug here?