It wasn't so long ago, recalls Napa Valley-based insurance agent George Hunt, that "insurance carriers used to say that insuring wineries is like insuring pig iron under water--what's going to happen to it?"But over the past year, according to Hunt, many insurers have become somewhat more cautious when underwriting insurance for wineries. He and other agents say that insurers are requiring more thorough onsite inspections, for instance, or more safety mechanisms to be put in place. Start-up wine...