[DrScump]

   a great support person is not that technical to debug a tricky API issue

A great support person is, and can, assuming s/he has access to source and, ideally, a build and test environment.

When in Support, I used to diagnose issues as far down the rabbit hole as I could within reasonable time constraints. If I could diagnose right down to the offending code, I would end up with a much better understanding of the code base (and, often, platform), plus I could win much faster response on rolling out a fix.