What Happens When Congress Abdicates to the Agencies?

Ezra Klein has an interesting long piece in Newsweek about the fact that Congress is broken (which should come as a surprise to no one) and that it's pushing off a great deal of its work onto the agencies and other bodies:

The architects of the health-care-reform bill, for instance, couldn't bring themselves to propose the difficult reforms necessary to assure Medicare--and the government's--solvency. So they created an independent panel of experts who will have to propose truly difficult reforms to enable the Medicare system to survive. These recommendations would take the fast track through Congress, protected from not just the filibuster but even from revision. In fact, if Congress didn't vote on them, they'd still become law. "I believe this commission is the largest yielding of sovereignty from the Congress since the creation of the Federal Reserve," says Office of Management and Budget Director Peter Orszag, and he meant it as a compliment.

Cap-and-trade, meanwhile, is floundering in the Senate. In the event that it dies, the Environmental Protection Agency has been preparing to regulate carbon on its own. Some senators would like to block the EPA from doing so, and may yet succeed. But those in Congress who want to avert catastrophic climate change, but who don't believe they can pass legislation to help do so, are counting on the EPA to act in their stead.

One thing I would be interested to know, however, is whether Ezra sees discernibly different outcomes when these issues are given over to the agencies. In other words, do bureaucrats make different decisions than lawmakers would if they were pursuing this work? And are those decisions demonstrably worse? No matter the answer, it's obviously still a problem that Congress isn't particularly functional, but I would be curious to see the results.