Well, I posted on page one, and got to test this out from my trip to Seattle this past weekend. I got to see an confirm some specifics. I had charged at home before my trip, and then set the charge limit at 60%, to make sure that the first charging stop would have to make that decision about going past the limit. I had no cell signal at the location (Baker City, OR), so I couldn't watch it in realtime, but I saw what it had done when I got back to the car.
(1) Yes, it blew right through my charging limit, without any notification.
(2) There was disagreement on page 1 about what it would then do. It does not continue all the way up to 100%. It was stopped when I got back to the car at 190-some miles, which is less than my 80%. So it was going by its "ready to go" mark, apparently, but its opinion of "ready to go" was only showing a 7% buffer at arrival! That sucks, so I moved the limit up and restarted charging to get more margin before leaving.
So it seems to be kind of the worst of both worlds. It doesn't respect your charge limit, and it still doesn't charge high enough.
(3) And someone mentioned about how it may be using the charge limit level to decide on its recommendations. Like if you have it set at 90 or 100%, it would try to go for really long charges to skip over Superchargers, but with a lower limit set, it might be trying for short charges and more stops. Not totally conclusive, but doesn't seem like the case. I was at Baker City, Oregon with a 60% limit, and it still decided to try to overcharge to go skip over Pendleton to get to Kennewick, Washington.