We were stoped over night on our way to Glamis at the Trump 29 Casino years ago and the DOT CHP rolled through the parking lot and stopped to talk to us because we had two rigs pulling doubles (FW & toy trailer combo). After measuring both setups (both under 65') and confirming proper licenses (both correct) and turn signals, tire tread depth, and on and on and on he stated we were good to go.
He then next looked at the three MH's that were with us and said "as long as I'm here I might as well measure those." Two of the three were over 65', one at 67' and the other 71'. He allowed them to unhook and no ticket as long as we didn't leave in the morning with the trailers attached to the MH's. After much discussion we decided to just make extra trips to get the trailers to Glamis and good thing because his buddy was sitting at the casino exit watching everyone leave in the morning.
On the trip home both MH's hooked to there trailers and headed home and have since travelled thousands of miles with no issues. I think it is best to be within the limits of the state you are registered but as far as getting ticketed I feel it is just the mood of the officer or drawing attention to your setup that will get you in trouble.