I trust that it is honoring DNT, but I can't see what use it can be if that is so. What more can it be doing over & above the weblogs that my original request would have created?

Nothing, it ignores your request. It doesn't ignore it when DNT is disabled. As Piwik ignores DNT requests by itself, I guess nobody bothered to disable the snippet on server side when DNT is detected.

That's a shame. Although I guess it is difficult to avoid the request if you have lots of static pages with the script link in them.

Perhaps we could have something like a <link> or <img> track flag, so my browser could decide whether or not to fetch the link based upon DNT settings?

The problem is that DNT isn't verifiable DNT should be done in browser and in the original website by not loading the tracking scripts at all.

ATM how it goes is that the DNT header is attached to outgoing requests and you "hope" that the 3rd party is discarding them.

You do know, that you do not need a dedicated tracking script to track you serverside?

Eh? they know that some one accessed resource X from IP address Y that's not tracking.

They know that someone accessed resource X from IP address Y from browser Z with language preferences A, encoding preferences B, SSL cipher suites C (when https is used), DNT preferences D, sometimes also protocol support E (when upgrading to SPDY or HTTP/2.0), having a TCP/IP fingerprint of OS F. I guess I still haven't covered it all.

Exactly, that's the sole purpose and that's how DNT works. It's nothing more than a voice "I don't wish to be tracked" and an expectation to be listened to.

Hmm...the idea to block all third party trackers by default and only allow 2nd party trackers (also with a few restrictions) could be interesting.

I'm guessing this is not what the EFF is doing here, though.