I think the takeaway on CC is that it will help FE for 99% of the normal drivers out there who will give no heed to other tips/have no more than a casual interest in using less fuel. It's about the most 'extreme' thing they are willing to do, based on observing my wife, parents, in-laws.

So telling people to use CC is positive for almost everyone. NOT for many of us here, though. If nothing else, it puts an upper limit (sort of) on their speed for most of a trip.

FWIW, I personally use CC religiously to ensure I stay at 60- the added benefit of DWL beyond that is minimal, and outweighed by the added concentration/effort reuired for me. I drove with the load for about 9 months before going back to CC, and my tank records show the lack of) difference. For me, the biggest boost was regularly driving as though my brakes were a last resort means of slowingthe car.