I don't know much about PWM or PDM, so maybe I've misinterpreted everything but I was under the impression that the blog post wasn't intended to be the ultimate solution for everything. I don't disagree that engineering should be replicated by other people to help ensure it all works rather than accepting stuff blindly, especially if it's vital for a projects success, but it looked like D@n was looking for better audio quality rather than launching rockets...
On a different note, it looks like from his main blog page that D@n was at some conference these past few days so maybe he hasn't looked at this thread in the meantime? I'm just a little confused since it seems like you were aware of this in one of your posts with the "across the pond" statement but then proceeded to reply several more times with some apparent confusion as to why he hasn't responded. Then again, I'm neither D@n nor you nor a contributor for this Forum, so I'm probably just putting words in people's mouths. Sorry if I've offended anybody.