There are different laws for each state - but, many have set the max overall length at 65' for non-commercial vehicles and non-commercial licensed drivers...so the set-up mentioned with the Subaru would be no problem in those states. I would check my local laws.
Would an over-length RV ever get cited? I don't know, but if there was an accident, it could become an issue.
While a remote risk, there can be a chance that police would set-up vehicle enforcement stations near where RV's collect...equipment enforcement includes weight/length/license checks.
Like, in the mountains near a very popular off-road area in SoCal, police where stopping RV's for this purpose. An acquaintance of mine (who was driving a MDT Super C and towing an enclosed trailer loaded with off-road toys) was ticketed for exceeding the legal weight allowance of his drivers license...His trailer's GVWR required an upgraded license type
Knowledge is power
Kim and Steve, Mustang LCDR (Ret), '07 Damon Outlaw #1193
I have seen gross intolerance shown in support of tolerance, Samuel Coleridge
WE LOVE OUR OUTLAW RV