Why would it kill you if you can do it "with ease"? How about admitting for the first time in your life you were being absolutely delusional about your abilities. That's the true reason you won't go for a 500 lb conventional deadlift from the floor with no straps: it's too real for you. You'd have to own up tp being delusional afterward.
I absolutely can deadlift 455 I pulled 405 using no legs no warmup and no hitching. But why? I don't deadlift heavy because I have a bum fucking knee there is absolutely no point. I could go into the garage unload the 405 to 225 do a set go up to 315 do a set then pull 455 but why the fuck do I want to do that?

What good is that going to do me other than trying to fuck up my knee ??
Lets say I go into the garage right now and do it do I get a cookie? Lets see you guys strain yourself doing some heavy deadlfts first. I said 100 times start a thread get other to particpate and I would do it but I am not going to be the only one.
Go pull 455lbs and put it on video then ask to see mine