In the almost 15 years of RV`ing I`ve never had an issue at an entrance ramp! I don`t know how or why so many here have issues? I keep my speed set around 67mph. this keeps me at the same speed as the semis rarely do I have to vary my speed by more than a couple MPH. I would much rather travel at that speed than travel slower and stay parked next to a semi for hundreds of miles! this also allows me to let in the people that don`t know how to merge at an entrance ramp. whether they are supposed to merge or not doesn`t matter to me, I would rather be the one to change lanes to let them in. it`s called defensive driving, which is probably why I have never had a close call in all these years.
Yes during rush hour you don`t have much of a choice, but traffic is usually traveling around 30-40 mph so it is a non-issue.
Yes I have traveled I65, several times!, all the way down to Louisville KY. I65 is one of the easiest drives out there.