Roger Simon has a fun column about the Ames straw poll, which he argues is a winnowing process that gives the media an excuse to stop taking certain candidates seriously. (Simon’s piece appears near a front page story about a candidate at risk of being winnowed.)
It’s possible to do well in Ames and then not flourish in the caucuses and beyond. But flopping at Ames does say something about a candidate’s viability. If people won’t vote for you when they are basically paid to, you’ve got problems.