> I think that requiring politicians to make public their statements explaining their the decisions on behalf of their constituents would be and unalloyed public good

Sure, this is fine, but that's very different from requiring all their interactions to be public. Put it this this: how often do you ever hear anything insightful or intelligent in a public congressional/senate hearing? It's always politicians trying to ask really stupid gotcha questions that will make them look good to the audience at home.