Twice in the last year (>13k miles total). One of them involved a truck pulling a fifth wheel that crept into my lane, but not far enough to warrant an emergenc

Twice in the last year (>13k miles total). One of them involved a truck pulling a fifth wheel that crept into my lane, but not far enough to warrant an emergency braking response. The other was a similar situation involving a vehicle merging in a short merge lane. I think the car was anticipating that the person was merging due to the short space that they had, but in reality they were slowing to wait on me to pass. Both involved the car jumping immediately to a full on panic braking type solution when no collision was imminent or likely. To be clear, I don't know that these involved dropping >10 mph either... but it definitely would have if I hadn't intervened.