Yeah I've seen guys do that rounded back row with the whole weight stack and they seem fine with it... I won't be trying it though
I get that issue, I sometimes scrape my knees on the way up... I guess you should concentrate on straightening your legs first... then pulling back... I concentrate on thrusting my hips forward and leaning backwards as I come up... you can always try the variations, stiff leg, Romanian or even just rack pulls
TBH I really hate doing deads, I did them yesterday and today I struggled to tie my shoes...I just do them because I know its a bit of a weakness because I spend all day sat on my ass