DnD does update dynamically with ap and % damage bonuses (and though I haven't tested, I'd assume mastery as well).
As for diseases, I was able to gain about a 10% increase in tick damage from last week to this week on Ultraxion by applying with icy touch and plague strike on the pull and then outbreaking when I had all my procs up for Gargoyle. I did have to reapply outbreak again midfight, but the gain on my first couple of minutes of diseases was pretty significant when compared to just outbreaking first thing on the pull.
Looking at log browser for my most recent kill, I had about 30% more powerful diseases for the first 2 minutes before I had to reapply, and thats ignoring the fact that they were also rolling under the crit proc off creche.
Here's the parse:
World of Logs - Real Time Raid Analysis
and this is the query set:
[{"spellNames": ["Blood Plague"], "eventTypes": [1]}, {"spellNames": ["Frost Fever"], "eventTypes": [1]}]
What annoys me most is that I could have been doing this since like 4.0 and just never thought of it
