Cory Doctorow (I'm a fan of his books) writes about an "Outstanding paper on the impact of ebook DRM on readers, writers, publishers and distributors" on his blog:
http://boingboing.net/2015/06/23/out...the-impac.html
The paper itself is a 40 page PDF on the Social Science Research Network:
http://papers.ssrn.com/sol3/papers.c...act_id=2620354
My take on their analysis is that it is not DRM per se that is the most insidious, but rather the multiple non-interoperable DRM methods that lock users into a single e-book ecosystem. I know that my own primary use for anti-DRM tools is to convert purchased epubs to a format I can read on my Kindle Voyager.