From Dave Detlefts' LinkedIn page, I think he may be part of the SPUR project:
January 2006 – February 2013 (7 years 2 months)Redmond, WA
* Transactional memory (see "STM.NET"; didn't become a product).
* CLR JIT team.
also, from Mike Magruder's LinkedIn page
Common Language Runtime (CLR)
I worked on the CLR, which is Microsoft's runtime for C#, VB.Net, C++/CLI, and many other languages. In total I spent 11 years on the CLR as an architect, dev lead, and dev, on projects which included the debugging and profiling services, exception handling, incubation projects on software transactional memory (STM), a new "minimal runtime" to be used at low levels within Windows, and a project to host JScript on the CLR. These projects involved development in C#, C++, x86/x64 asm, and code generators from IL to x86/x64 asm.
of course it was 10 years later.
btw: sad to know Dave Detlefs and Mike Magruder have left CLR team recently.