Ultimately, the Celtics' "dephth" is their flaw. Too many role players dependent on meaningful minutes in order to be in the flow.
Bass, Green, Terry and even Lee need 25-30 minutes every night to be in the flow. None of them are playing spectacular, and definitely not consistently. Players like these need minutes to come out of a slump, but get their minutes cut instead.
It's the double-edged sword that is "depth".