When applying for academic jobs in the US, one is often asked for a recommendation letter from someone who can attest to your teaching abilities. Suppose someone has been involved in various workshops, programs, discussion groups, etc. about pedagogy through a Center for Teaching Excellence (or a comparable office) as a graduate student or postdoc; is it acceptable for a non-teaching staff member from this center, who has facilitated such activities, to write a teaching recommendation letter for academic jobs? In particular, how are such letters perceived by hiring committees?
Edited to clarify: I was envisioning that such a letter would be in addition to a teaching letter written by a faculty member in one's department.