A slightly adjusted diet

JimBobby is close to nailing the best analogy for the Cons' reliance on intensity targets. But it's worth noting that even he's a bit too generous, as the Cons' intensity targets won't even ensure that emissions growth slows down if industries decide they can more efficiently meet the targets through increased production.

So let's tweak JimBobby's analogy just a bit.

The Cons' plan is the equivalent of a man being told by his doctor that he's overweight, out of shape and needs to start unclogging his arteries immediately, and saying to himself: "I need to start eating healthier. So I'll count my cholesterol carefully, and make sure that I take in 20% less cholesterol as a proportion of the food that I eat."

But then, he decides that he enjoys his current diet too much to give up any of the foods he currently eats - and instead chooses to eat an extra meal a day of zero-cholesterol food. While he gets a few extra nutrients, his weight increases all the more, and his arteries continue to clog. And the end result is an even earlier grave than in JimBobby's analogy.

Again, the ultimate folly of intensity targets is in the "extra-meal" possibility - the scenario where businesses meet their targets - and perhaps even earn large quantities of credits by exceeding their targets - through ramped-up production rather than any conservation at all. Politically, it may be a smart play since it could encourage some businesses to increase production in the short term, with the need to actually reduce emissions left until far down the road. But the end result is nowhere near the diet that's needed for a healthy planet.