Ya know... he brings up an amazing friggin point with the concept of "open-source IE". I actually believe MS SHOULD do this for IE6 only at this point in time. You guy's (MS) are going to end support of IE6 & XP etc soon enough SO Microsoft should, I believe with all my heart and logical conclusions, open source IE6 and given to the open source community to work on as a modern IE6 clone project to improve on as an option alternative to the actual IE6 rendering engine and JS Engine built into XP which is going to EOL.
The whole IE infrastructure and code I think is already all replaced with new-generation code and concepts so allowing an open source community to work on an IE6 clone built directly from the IE6 source and built to uphold IE6 terrorizing situation while helping a built-in IE6 -> modern web shim wouldn't infringe on any current generation stuff for IE9+. As IE6's stagnant web problem that Microsoft has created without malice is indeed still a massive problem, and everyone still on XP is making this be a huge issue continue to be an issue.
So, for administrators that must keep XP in-house or for home users, allowing an IE6 clone to maybe shim the architecture of IE6 while maintaining problems which are "bug-as-a-feature" status may actually help the web move forward just even a little. Doing so would also indicate that Microsoft may actually want to help dig the WWW out of the hole it accidentally created by showing good intention to the world by open sourcing IE6 by itself and re-invigorating just a tiny bit of never before seen trust seen before out of Microsoft history.