As far as I know, DoNotTrackMe does more than just adding a Do Not Track header in the HTTP request - I think it actually identifies common advertising scripts (javascript) and strips them from your pages on the fly/blocks them from loading/communicating.
I will try reading more or look into the source code when I get a chance and see - but I think you are incorrect on that. You are correct about the Do Not Track header having "no teeth" though - it has been proposed for some time and is finally being implemented in browsers - but the other half of the problem (servers hosting sites/companies) have no legal obligation to pay any attention to the header at this time. AFAIK
Thanks for that, I didn't realise there were different do not track thingumies.