I go for a ride on the CCT every now and then, and from the article, it sounds like speeds will be enforced on the parts that are busy enough that you usually can't ride faster than a few miles an hour anyways. The only two places that ever are very busy in my experience are down by the boathouse in DC (near one end of the trail) and up near Bethesda (the other end). In between you have about 7 or 8 miles with only a few access points. I almost never see families in that stretch.