.OSX/environment.plist was the culprit - but why?

Okay. I am suitably humbled: it was the environment.plist file. Now, 
would someone please tell me *why* it causes troubles? I originally set 
it up in order to pass some non-standard BIBINPUTS paths along, but it 
never seemed to be read; on the other hand, now I find that this was 
the source of my woes. "Answers, Jim, I need *answers*!"
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WB Tuladhar-Douglas             +44 (0)7739 872 398
Wolfson College, Oxford                 
will-rOWMpZt0XeWGglJvpFV4uA@xxxxxxxxxxxxxxxx