Did not know it was forbidden and was never an issue until about 10 years when the normal 50 degrees was increased by some manufactures as a reason to buy their product. It's less of an issue with gassers as most have a much shorter wheel base than a DP.
Mine is only 50 as Monaco uses a Dana truck axle... plenty for a short semi tractor. When I need to make a harder turn I'll do it in two or three steps, backing up a few feet with the wheel turned the opposite way increasing the turning radius... helps that I can back up without unhooking.
