Blacksheep,
I recall being taken to task by a rather snotty Captain and being soundly verbally chastised for speaking directly to engineering people. That sort of attitude ought to have died along with liveried chauffeurs and personal slaves.
You may be pleased to know that I fought my corner and told said Capt that if he didn't like it, he could find another First Officer.
CRM is supposed to cure all of this sort of garbage.