For what it's worth, I do use deficit deadlifts in intermediate and advanced lifters. Rip is right though, if you pull from too much of a deficit, then the lift is just too different and you won't get any carryover. When I deficit deadlift, I will often have my lifters pull from a 2-2.5" deficit on week 1. The back angle doesnt change alot at this small deficit, and it seems to help lifters to initiate the movement with the quads (knee extension) a bit better. One week 2 they pull from 1-1.5" deficit. And on week 3 they will attempt a PR pull. This seems to work very well for myself and my lifters.

A 1-1.5" deficit doesn't matter much at all when you deadlift 315. But I can guarantee you that it matter a whole bunch when your deadlift is 700.

Matt