When I used to be a bigger puller in the early 2000's I relied exclusively on the sumo stance myself.
you are right, Martin, about the load on the legs with sumo. Its a much more leg and hip oriented pull than conventional, and it used to work well for me.
And RDL's rule, I do them myself. Love them...
Dave, I haven't done deficit work since those days at all, makes me think I should try it again and see how it helps me. I really want to get back above 600# again.