I know sometimes you can get him to keep fighting you in melee and never scream (seems to never dive if he stops screaming)
read somewhere here you can do it with a rogue's hook & tackle spam every time he starts. also seen him glitch in one spot and be exposed to ranged fire but as soon as a melee hits him, he'll snap out of it and dive. that usually happens on those steps in the middle area when you're at tevinter ruins.
when i've solo'd him as AW or legionnaire on threatening, there is always a point where he stops diving and screaming and lets me get about a good 1/4 at least of his health down by sticking with melee against me.
anyway, anyone having issues with DC dodging, I'd recommend doing a solo routine run with whatever level character they feel happy to be able to tank mistakes with and just practise the run and single jump to when you see the cloud above your head. Once you have it down, you'll never need to bother taking abilities just for dealing with DC again.