Exactly. How can someone with no coding background whatsoever even possibly predict timelines and constraints without understanding the fundamentals of programming, let alone understanding and having experience with specific programming languages. I myself code in PHP/jQuery/Javascript and report to someone who has a Java background. He may not have a background in PHP, but has an understanding of what programming involves.

And to make things better, because he has coded in a top tier 1 company, he understands what it means to code in bits and pieces and to break down a project into small chunks of software in order to build the bigger picture. And this is the basics to being a good Project Manager.