It seems to be that Professor Diamond's comments are a legitimatization
of the bias built into the core vs. non-core vs. heterodox journals.  It
reminds one of another "time is scarce" saving mechanism used in the
1950s-60s in the US when hiring workers:  if you are white you are
alright, if you are brown stick around, but if you are black, get back,
get back, get back. 

Fred Lee