Not really a "phantom brake" incident thoughIt happened again this morning on my way to work, same circumstance. Semi in the middle lane of three, I was overtaking in the left lane. There was nobody behind me so I let the car do its thing to see what it would do, it hung back for 10 seconds at which point the semi signaled and moved into the right lane. About 5 seconds after it got into the right lane my car tentatively accelerated back up to speed.
Not really a "phantom brake" incident though
Cautious for sure
It seems to be getting better in my experience. Happens less often. The getting dragged into the right side on ramp is also a problem, and equally dangerous.