I'd echo everything everyone else has said about the blow off valves. When the pressure gets a bit high in the air system, it blasts a little bit out to keep the pressure regulated. Nothing to worry about.
I do know that many companies/manufacturers have governors on their rigs too. I used to drive school and charter buses in college and whenever I'd go on an interstate trip, I'd literally drop my foot on the floor for hours on end and was bouncing off of the governor the whole trip while still being passed all the time. Hills didn't help either.
I generally generally move over just as a courteous gesture. Plus, it also reduces the risk of them running into me should they decide to not check their blind spot, or if there is an obstruction on a short entrance ramp like a bridge rail or something.
Technically yes, but I always want to lay down a spike strip for people who do that because they're ultimately cutting everyone else in line. That significantly worsens traffic jams too. If everyone waits until the last second to get in the correct lane, everyone will be stopped trying to squeeze into holes that just aren't there and everyone will be stuck. Conversely, if everyone would make the effort to file into the correct lane before absolutely necessary, there would be no bottle neck and traffic would flow much quicker and smoother when the lane ends.
'97 Vulcan 1500 Classic 88