Okay, let me see.
One way is you weigh both truck and trailer as a unit, then you drop the front legs and raise the trailer enough to take all the weight off the truck. That gives you the complete trailer weight and then some math will give you the pin weight.
The other way is basically the same except you pull off the scales drop the legs the same way but you unhook the trailer. Now you weigh the truck and simple math will give you the pin weight.
Neither one seems unduly complicated to me. With one you don't drop the trailer and the other one you do. Big deal. Either way works, nothing much different between the two.
