And going back a bit: the other underlying fact is that there will, eventually, be a bill or bills that passes. It's not quite 100% certain, the way it is with government shutdown or debt limit showdowns, but it's awful close to certain. The bill or bills may come before January 1 (very unlikely now), in early January, in late January, in February, even in March...but the odds are overwhelming that sooner or later something passes that will undo the bulk of the fiscal cliff tax increases, take care of the Doc Fix and the AMT fix, and do something about the sequester, among other things.
Moreover, everyone involved knows it. Well, maybe not Michele Bachmann and Louie Gohmert, but just about everyone.
So why am I not really cranky? Well, it is possible that a deal will be struck in the Senate that could work; the eventual deal needs the support of Barack Obama and John Boehner, but they don't have to be the ones making the deal (quick reminder: there is a possibility on the table that Republicans in the House could vote present and force Democrats to supply all the votes; that still means Boehner supports a deal, even if the way the support is expressed is by not voting against it). So I'm not ready to completely write off Weisman's article. And I suppose Silver's post is okay as an intellectual exercise; it just doesn't tell us much about how we'll actually get through the fiscal cliff.
But, yeah, the first thing to keep in mind is that something will eventually pass, and it will be a deal that mainstream Democrats and mainstream Republicans can live with. Any analysis of the situation that doesn't accept that starting point is probably not helping us understand it.