Mechanically, does the Jefferson squat offer any advantage over just wide stance squats? It was as if Kai was doing "weird" excercises to make it seem like he was doing something novel? I remember he said he started all back workouts with dips which seemed weird to me but the other day I looked at a nautilus dip machine at the gym and I think it said it worked the lower traps?
Regarding pull ups for back, do you guys really do overhand pull ups instead of pulldowns? For me it's such a heavy exercise I feel like I can't do even a single rep the way I'd like to, the range is real short.
Guys that do them a lot with good weight advise that the closet feel to them is probably front squats. It's an old 1800s lift that was around before squats, etc.... were common place. The inventor was Charles Jefferson, an old circus strongman whose act was a lot of deadlift and partial deadlifts, etc..... mainly.
The only other argument for them is that it's probably safer than deadlifting because of the self limiting nature of the lift, and because traditionally there isn't much rounding of the back, etc....
Quite frankly, with things like trap bars, etc.... why bother unless you're an "odd lift" guy.