Single Crew B190 Operations
I can only speak for B190 operations, but I know a lot of guys are using the alleged "loophole". In fact, it is not a loophole at all. The POH specifies it is a single crew aircraft, but it has certain conditions. If you look at the limitation section they say:
1.) An operative three axis auto-pilot system must be installed.
2.) No more than 9 pax are allowed.
3.) Even when flying with only 9 pax, the other seats have to be disabled with the approved kit.
Operatos just look at the first line of the POH and think, "GREAT"! Nobody ever bothers with the rest...