I have been towing tandem bumper pulls for many years. You need to be diligent about the weight transfer on your tt when towing doubles as it will lessen the tongue weight. Other than alot of the misinformation on here like it being illegal in Ca (its legal there) it can be done and done safely. Instead of random sites that list towing laws you need to check with each state you plan to travel in. Be prepared to have people that have no clue to come up to you when stopped for gas etc and tell you its not legal or not safe. If you have other questions pm me and i will answer as best i can as these threads on here can get quite lengthy with lots of misinformation.