PUBLIC MARKS from ycc2106 with tag pollution

There's a new proposal ("URL shortening that doesn't hurt the Internet") floating around for using rev="canonical" to help put a stop to the URL-shortening madness. It sounds like a pretty good idea, and based on some discussions on IRC this morning, I think a more thorough explanation would be helpful. I'm going to try.

La Terre se réchauffe en raison de l'accumulation de gaz à effet de serre générés par les activités humaines. Le principal de ces gaz est le dioxyde de carbone (CO2) qui résulte du gaspillage des combustibles fossiles, en particulier du pétrole, d

Gee, this is depressing! I consider myself to be someone careful. I do recycling, avoid the car in town, try to use local products, try to not to wast water, electricity... but even with this it says if everybody was like me we would need 2.5 planets!!! Or maybe I made a mistake, I hope so, some questions are quite precise.