The tech manager is an apt analogy for me because I am currently working on hiring a new boss for (myself and) a team of programmers, high performance computing consultants and geographic information systems specialists. Each applicant has different levels of experience in these areas, but I think its safe to say that there are few people in the country that have good GIS and HPC experience.

Different groups need different managers/leaders. I could argue that I need a manager that understands my work so that they can guide me appropriately choosing techniques/languages/architectures. I could also argue that we have a diverse team of experts that self-manage well, and that we need a manager who is a good advocate for the group and good at dealing with the politics of university management, who won't micro-manage, and can deal with all of the admin requirements so that our team can program, make maps and support HPC customers. I agree that they should probably have some kind of a tech background, but I don't think you need to have been a professional programmer to manage me.

* Hopefully no one from HR, and none of the candidates read this.

* * Actually if a job candidate gets an advantage by reading a HN comment then I would consider that in-bounds for their interview prep in this case :)