...., the total weight of the vehicle and the trailer together can’t weigh more than 3,500 kg. .....
the rediculous thing about this legislation is that it's not the actual weight, but the weight it could be eg you'll be over the limit of 3.5t if you towed an empty car trailer that has a MPTML (max gross weight) of 2t behind your 2 tonne car. That's like saying, I'm booking you for speeding because as your car will do 150mph you MIGHT speed!

I agree Andy. I know we have diversed slightly but if I've understood the current towing rules correctly, my son can tow my caravan with my omega but not with his 4x4 truck.
The Omega has a kerbweight of around 1800kg, my caravan has a MTPLM of 1500kg so equates to around 3300kg combined, so I assume this is legal for someone who passed their test in 2003.
His truck has a kerbweight of 2200kg, so with my caravan hooked up to it he is looking at the wrong side of 3700kg. This is obviously not legal without the B+E entitlement.
As we try to encourage large heavy car/ small light van combination, this seems to defeat the object of this. I can only assume that somebody somewhere wanted to prevent a 17 year old towing a Swift Conqueror with his Range Rover Vogue. Am I missing the point here or have I read it wrong on the directgov site. I get more confused every time I read it and it's all immaterial really as he is going for the B+E thing anyway.
Passed my test at 17 in May 1979. (and yes, I am very nearly 50,

)
Regards
Alan