Hi Adrian,
I think the principle of EPCs are good. What is lacking, as we have both experienced, is largely down to two things: proper advice; and a lack of real energy data rather than theoretical performance. Until we know how much carbon buildings are actually guzzling what's the point really?
You're spot on in identifying the serious blockages that are stopping us really tackling the problem of the existing stock. The UK Green Building Council has done a lot of work on finding realistic policy ideas to deal with this - http://www.ukgbc.org/site/news/showNewsDetails?id=104 - which was submitted to government last month. Let's hope there's some action on this. But don't hold your breath.

Indeed. To look on the positive side, there is now a mechanism in place to look at properties and maybe in time the advice and possible modifications will improve. And I'm working on helping people know how much carbon their building is using ;-)

But I'll feel better when the Government starts acting rather than continually talking about acting. (And obviously I'm not holding my breath...)