Huh, that's pretty interesting. It reminds me that I had a workplace experience related to this recently

I was working with a client based in another country (which made me a little less certain about customs/etiquette), and our relationship was a little similar to manager/subordinate (esp. because I had a peer in meetings which he would somewhat direct).

For the first several months we were actually pretty strictly non-interrupting in conversation, but there was a transition at some point because a lot needed to be communicated and everyone involved was very interested/engaged. I think he was a bit taken aback at my first interrupts (which were e.g. to let him know I'd already heard about something he was trying to tell me), but once he saw that I also very readily yielded if he ever wanted to interject, our style of speaking morphed so that cooperative interrupting became commonplace (and our conversations became more fun :).

I think in a situation like that it's inherently a bit risky because it can signal things about power dynamics, but if you actually play nicely with it, don't use it for your own benefit, just for efficiency, it can also be a way of upping trust level (specifically because it was something risky, they had to trust you some, but it turned out fine).