50 feet is VERY dangerous. I've seen tires blow out on trucks that would go through (or at least damage badly) windows of drafters. fwiw I know you said not to say anything but I feel people need to be warned. A little bit better MPG isn't worth the very small, but very real chance of losing your life.
Vehicles at interstate speed travel at a rate of about 100 feet per second. You're supposed to maintain at least a 2 second separation. At 50 feet....you're deep into moron territory.. I was going to add some comments on your intelligence and lineage, but I think that your post clearly speaks for itself. I can only hope that you draft exclusively off of large trucks and don't carry passengers, especially young children. LEO's are starting to crack down on folks like you. In Oregon for example, they have special equipment that monitors following distance. Less than 1 second, and you get zapped with a heavy fine. It's a shame, really. LEO's should be kicking in the doors on meth labs, and giving rapists a really, REALLY good reason to buy their soap on a rope instead of wasting time trying to reduce the beneficial side effects of natural selection.