Graham Lee, a Mac and iOS developer, writes about Cocoa, Objective-C, software architecture, and the habits of software development.
HN commenters cite it when questioning the evidence behind a software engineering claim, pointing to a detailed post that tracks down the original sources.
The studies supporting it have apparently been somewhat hard to confirm, a lot of the source material used by McConnell seems to be from secondary sources and self-referential. [1] is a detailed blog post where the author tries to track down the original sources:
[1] http://blog.securemacprogramming.com/2012/09/an-apology-to-readers-of-test-driven-ios-development/