Escort is possibly a wrong example but for general trailers, caravans etc B+E does not always apply.
I sat the B+E and the trailer was a tow-a-van twin axle behind a transit. I then sat my cat C LGV and my employer wanted me to tow a mini excavator behind a 10ton truck, again this was a problem as I was only allowed to tow 750kg!! So they sent me for C+E (artic) and now I can tow a trailer behind most things!!
I have sat a theory test for Motorbike, Car, Truck and also a practical test for motorbike, car, car towing, LGV, HGV !!!
Its a bit of a joke.!