[JackC]

> Would you rather have your software written by a foolish programmer who is pleasantly tactful or a competent and conservative one who is tactless?

This is a false dichotomy. Interpersonal skills are among the skills necessary to work on a project that involves more than one person. That covers most of the interesting ones. If there's a successful project with someone who lacks those skills, it's because other people are covering for them -- just like a successful project with a foolish programmer. Sometimes that person makes up for it with other things they bring to the table, and that's fine, but don't pretend a weakness is a virtue.