Exactly, it's to drop past bench. We used to use a fairy good amount weight. And no, never seen anyone screw up their backs. Not that it can't happen, it's just unlikely.
Are you just setting out to deliberately fuck up peoples backs?
That ridiculous video last week of people sitting down and rolling their spines about whilst squatting , now this bullshit.
Bending over at the waist alone puts a hell of a lot of strain on the low back due to just the weight of your head, now to add an extreme extension and fuck around lifting weights whilst in full extension is idiotic in the extreme.
I seriously wonder if you are just trolling here.