I've not heard it put that way, but the A-shaped hug is what I always assumed my ex wished I would give to other people. But honestly, that feels so, so awkward - if my interlocutor is the sort of person to whom I'd only give an A-shaped hug, than I'm not going to bother.

Anyway, this woman initiated the hug, so I'm not terribly worried about the fact of the hug. But there are a number of common interactions that you have to tune specifically to manager/subordinate interactions, and physical touching is one of those things. So I find that whenever I physically interact with one of my subordinates I find myself carefully reviewing the interaction after the fact to make sure that it was handled correctly.