I like the idea behind the crown changes, but Phreak realizes the difference between 75% DR and 40% is insane right? Like really really insane? You take 140% more damage at 40% DR compared to 75%. And duration only goes up by 66%. And the AP changes is pretty net neutral or large nerf for artillery/burst mages.
So I don't really understand why it's getting gutted. Like those are huge nerfs.
Calculating DR that way only makes sense if you'd actually keep it the whole time before dying.
Like in your model, 99% DR is twice as good as 98% DR. If you had it permanently, I'd agree; you'd live twice as long.
But this isn't a permanent effect. It's functionally a shield. 80% DR for 1 second is equally as good as 40% DR for 2 seconds if you're taking linear DPS. But it'd be 3x as good if it was permanent.
That's the crux of it: In generic solo queue, you're taking somewhat linear DPS, or even scaling since people will hit you later after the Leona or Thresh engage. Meanwhile, highly skilled teams can actually frontload all their damage via coordination.