Take this teleworking for example. What if for one company telework is a no-brainer they'd like to do anyway, and in fact could do double it. But a second company it's completely unworkable. They will be completely unproductive at home. If instead of mandating behavior you put a price on it--and let people trade it openly. If it is extremely advantageous economically for you to work in an office every day your company is free to buy credits from the company who teleworks six days and sells you three days of credits. (In the commons, you don't force a sheepless peasant to stand in the commons twiddling his thumbs, you let him sell his share of the use of the commons to someone else who can use it more.)
Of course at the meta level this is still inefficient because there's other sources of greenhouse gasses. So trying to force them by regulating just telework on its own in a vacuum is still a stupid idea. This is why general carbon credits are the way to go, because you don't have some omniscient (supposedly but not really) government bureaucracy deciding how "best" to allocate the limited emissions. The government is great at (with science's help) deciding how MUCH aggregate emissions is acceptable to society--that's the core thing the free market sucks at. But then, once external costs are internalized in the market, the credits can be freely traded and the market figures out the most efficient methods of reaching that limit. Free market is a powerful, but amoral tool. Good policy points it in the right direction rather than try to replace it.
If Machiavelli were a hacker, he'd have worked for the CSSG. -- Phil Lapsley