I try to stay out of everyone's way, but even at 70 mph, the "Fast-packs" are on me so quickly that they can pinch me between them and slower traffic.  On some of the two-lane each way, divided highway, merging traffic is especially dangerous, because the merging vehicle under-estimates the speed of the packs.  The packs pass on my right, and pull in front of me almost scraping bumpers, while weaving back and forth between lanes.  The slower lane is often following too close for me to fit in between them.  And some of the slow traffic is so slow, that there is no safe way to merge with them, from 70 to 45, while some "road-rage" clown is pressing my rear bumper , at 20 feet or less.   I strive always for as much distance, front and rear, between me and the packs.  You see that lone vehicle "way ahead, or way behind there"?  That's me!  I'm happy to note though, that almost all of the 18 wheelers stay very close to the posted 65mph.  At least I don't have to contend with them also.