I don't know what rpg.314 is referring to either, but I can think of at least one thing that can break both the overdraw removal and the submission order independence of TBDRs quite badly: Virtual Texturing.
Especially if the form introduced by AMD (
http://www.anandtech.com/show/5261/amd-radeon-hd-7970-review/6) and made part of DX11.2 becomes the preferred form: this is a form of virtual texturing where, at the shader level, the texturing operation returns as part of its result whether it hit an unmapped part of the texture, and where the shader itself is supposed to record any such hits in a data structure on the side.