Firstly, you worked on PHB2 in 3e, I believe, was there any awareness at the time of how utterly problematic the spell ‘celerity’ would become for optimizers?
Secondly, Keith Baker has said that he’d be willing to write unofficial Eberron books in 5e if he was given the ability to do so by WotC, Planes and Oceans of Eberron are the two I recalling him mentioning as ideas. If Eberron doesn’t make it into 5e all that soon, what do you think the chances of this happening are?
mikemearls31 points20 days ago
Not that I’m aware of. Our release schedule in the past led to highly segmented work. For instance, I had no insight into the spell chapter, but did a lot of work on the feats. Few of those feats were ever tested. I believe the spells fell into the same thing. The testing approach to 5e grew directly from my experiences on 3e and 4e.
I would not be surprised to see Keith working with us in some capacity in 2018.
from discussion AMA: Mike Mearls, D&D Creative Director.