Also somewhat related, if there's a slow vehicle in front of you when you're going down the on-ramp to the interstate -- slow down even more so you have many car lengths to merge.

Nobody else I've ridden with will do this (I've suggested it). Instead, they tailgate the slow car, curse like mad, and then almost cause a wreck when the try to pass the slow car in full-speed traffic as soon as they enter the interstate.

If you leave enough space you can easily get up to interstate speed and pass them quickly and effectively.