Why can I drag but not move?

I keep encountering the problem where I select a bunch of lines and points on a sketch, I then invoke move some mm in any direction, and it refuses to let me, complaining that it can’t resolve the constraints or something like that.

Then, after selecting the same elements in the exact same way i proceed to manually drag them the same number of mm in the same direction and it has ZERO problems.

I’m sure there’s some programming logic that explains this, but as a user it’s maddening.

Is this a bug that’s already in your list, or … if this is actually a sensible behavior is there some way to convey to users WHY this makes sense, because I’m a developer and I still don’t get it.