The argument is that the electorate can't vote on policy unless they can see those policies in action. Voters can rest on the dogmatic idea that private markets solve everything without ever having to experience the effects of privatized social security.
Elected officials can rely on dogma too, styling themselves like sports teams, knowing that because actually accomplishing something is off the table for both parties, they have to appeal to voters almost entirely by signaling their virtues.
Yes, it would mean rapid fluctuations in policy, but the idea is that we need to inject some volatility so we can see what works and what doesn't. Obviously, this can lead to problems, like a majority party implementing policies which restrict the electorate or affect populations that can't form a strong voting coalition, but I'm not sure this is worse than what we have already.
Further, I'm not really sure how we're supposed to reevaluate "we." That's a neat soundbite, but what does that mean? What are you suggesting we actually do? Alter the electorate? Split the union?