If it is a problem it's gotten worse with all the hybrids and hypermilers out there. In a hilly area, cruise control'ers and momentum conservationists don't mix. I like a steady 65 mph which doesn't play well with drivers who slow to 45 or less at the top of a hill then build speed downhill. Do that if you must but move over for those who can continue to drive safely at the limit.

Sixto
87 300D