I also find it a frankly baffling idea.
I don't want my plumber to use common sense. I have common sense, and I can't fix a leaky dishwasher. I want my plumber to use Special Plumbing Knowledge, experience and the right tools. Which amounts to common sense for plumbers, but has nothing to do with me, no matter how many pipe wrenches I own and how many faucet washers I've changed over the years.
I don't want my cancer surgeon to use common sense. I have common sense, and I couldn't find a tumor if you julienne sliced my body open for ease of search. I want my cancer surgeon to use Special Surgical Oncology Knowledge, experience, and the right diagnostics and medical imaging. Which amounts to common sense for cancer surgeons, but has nothing to do with me, no matter how many times I keep going under the knife before this shit finally kills me.
I don't want my airline pilot to use common sense. I have common sense, and I couldn't land a plane with a scorecard and a map. I want my pilot to use Special Pilot Knowledge, experience, and a strong understanding of her well-maintained aircraft to bring me safely back to ground. Which amounts to common sense for pilots, but has nothing to do with me, no matter that I've flown something like two million air miles in my life as a passenger.
Need I go on? And I'll bet none of the politicians calling for "common sense government", and none of the voters eager for their message, want "common sense plumbing" or "common sense cancer surgery" or "common sense airline piloting." Yet the machinery of government is every bit as complex and intricate and baffling as plumbing, tumors or heavier-than-air flight. Frankly, a lot bigger and more complex.
I want government by people smarter than me, not government by folk wisdom and simple aphorism. Thoughtful analysts, policy wonks, subject matter experts, budget mavens, and all their ilk. There may have been a time and place for the citizen-legislator, but I'm not sure that wasn't ever a myth, at least in this democracy. If common sense could run government, then every cab driver who knows how it should be would be sitting in Congress.
Give me expertise over common sense, every single time.