The "women" just got done deadlifting... Looks like the "Kroc looking" Victoria Long got injured.
Crazy numbers though...

Firstly, those numbers are wild. I don't want to take anything away from those gals.
Secondly, I'm curious exactly how the elephant bar deadlift translates to a conventional bar deadlift.
The Elephant bar is 295cm / 9'8", compared to the conventional Olympic bar, which is 220cm / 7'3". And those 45-lb "deep dish" plates they use at the Arnold are thicker than normal 45-lb weight plates that most commercial gyms have. The Arnold plates are 5cm thick [1.97"], as opposed to 3.5cm thick [1.38"]. Those plates have beautiful craftsmanship.
Anyhow...
The different dimensions of the Elephant bar and the thicker plates produces a different "type" of deadlift. Specifically: the bar bends until your hands get to about your knees, and then the weight starts pulling off the ground.
Initially, that flex can throw you off, and cause you problems, but once you are able to control the flex, the lift becomes more of a [very] low rack pull.
Not, like, an above the knees wrap pull, but a knee pull from about the lowest rack/pin possible, starting below the kneecap.
For me personally, it makes all the difference. My max deadlift [with not great form] is 555-lb, but I was able to get 585-lb on my first attempt with the Elephant bar [with belt/straps].
Not to diminish any of those ladies - I've never gotten 600-lb on the Elephant bar [although I've only tried it once]. But for a person like me with short arms [70" wingspan], starting the lift at ANY height above the ground helps me.
With my arms being the length they are, my deadlift start position SUCKS. I need to start in a very low - sort of "squatty" - position. And as my videos show, I don't use my hamstrings when I deadlidt.

It's all back.
So I am much better at rack pulls for this reason, and I lift more using the Elephant bar for that reason. Again, once you learn to control the whip, you will lift more on it. For me, I lifted more on it right away.
I would say you can get...up 10% more on the Elephant bar vs. Conventional bar.
NOT to diminish any of the lifts of the gals above. Most of them are stronger than me, so I won't talk - but I would say a 600-lb Elephant bar deadlift = 545-lb standard deadlift.
So Lucy Underdown's 666-lb is probably equal to about 605-lb, with the entire women's range being 469-lb to 605-lb, if all the lifts were on the standard bar. And the average for the women is 587-lb, which would be about 534-lb on a standard bar.