What are the differences and which is better when vertical jump is the goal as a supplement to squatting?
I think conventional is better when squats are performed as well. The trap bar deadlift is a lot more similar to the squat than the conventional one, so it is only the logical conclusion that normal deadlifts are better since they target the body in a more distinct fashion compared to squats.
The main difference I see between the two is that in the trapbar deadlift the weight can be kept closer to the center of mass of the body resulting in a leverage advantage and a more upright torso in the starting position. This would lead to a different focus of muscle groups involved.
^^ exactly. If you are already squatting, a traditional "style" deadlift will target the hamstrings and glutes more than the squat does so it is a good supplement. However you can perform a trap bar deadlift similar to a rdl or traditional dead, but the actual deadlift is not a squat, its a pull. If you were using either or and only doing one, without squatting, the trap bar would be a good option with a fairly erect torso position. Coming all the way to the floor and stopping will take away a lot of the reversal benefits that you get from squatting, but you can remedy this by stopping just short of the floor and reversing.
