While many of us strive to build "light"....I don't believe that it has been discussed as to what is "too light", and is there a "too light" point. I've been on 2 lane roads, with the driver window open, and had the back window blown out of a hatchback by the pressure from a passing large truck at speed. It pushed my utility trailer all over the road and with a light tow vehicle, made it a handful at the moment. I'd also bet that many of us have experienced being pushed about by either cross winds or passing vehicles.
I would think that a super light trailer while giving excellent gas mileage, may be an issue on the road in less than perfect conditions. Crossing I 80 in Wyoming at times, it's not uncommon to find both large trucks and RV's on their sides and at times, they flat close the road to trailers because of winds. While our trailers aren't as large as a semi trailer, many of our tow vehicles don't have the weight to control the sway either. Is anyone concerned about too light?...sort of thinking about the foamie type builds. For me...I hate towing in cross winds even with a standy at 1400#. Any thoughts? Doug