ACR COMPANY OBSTACLE DEP PROC IN CONFLICT WITH RDU VECTORING CRITERIA CAUSES FREQ DISCUSSION.

Narrative

RDU COMPANY ARPT PAGE SHOWS AN OBSTACLE DEP PROC FOR RWYS 23L/R CALLING FOR 'CLB RWY HDG TO 3000 FT BEFORE TURNING L.' WE BRIEFED THE PROC; AND WERE ASSIGNED RWY 23L FOR TKOF. OUR DEP WAS THE TARHEEL 6; WHICH REQUIRES A L TURNOUT TO INTERCEPT RDU 176 DEG RADIAL. PASSING APPROX 1500 FT AFTER TKOF; TWR ASSIGNED US A HDG REQUIRING A L TURN (I BELIEVE THE HDG WAS 120 DEGS). WE ACCEPTED THE HDG; BUT TOLD THEM THAT WE WOULD WAIT UNTIL 3000 FT TO MAKE THE TURN. TWR ASKED WHY WE WERE GOING TO WAIT; AND WE TOLD THEM OF THE OBSTACLE DEP PROC. THEY SAID THAT THEY HAD BEEN TOLD OF THE PROC IN THE PAST; IN SIMILAR CIRCUMSTANCES; BUT THAT IF TWR TELLS YOU TO MAKE THE TURN; IT'S OK TO DISREGARD THE OBSTACLE DEP PROC. WE TOLD THEM THAT WE DIDN'T THINK IT WAS OK TO DISREGARD A PUBLISHED PROC. THEY TOLD US TO DO WHAT THEY TELL US TO DO; ETC. THE EXCHANGE OF PLEASANTRIES LASTED UNTIL ABOUT 2900 FT AND WE MADE THE TURN TO THE ASSIGNED HDG PASSING 3000 FT. TWR DID NOT SEEM TOO UPSET; AND DIDN'T INDICATE THAT THEY WERE GOING TO FILE A COMPLAINT. I AM CONFUSED AS TO WHETHER WE ARE SUPPOSED TO FOLLOW A PUBLISHED PROC UNLESS YOU'RE RESPONDING TO AN EMER SIT; OR IF IT'S OK TO DO WHAT A CTLR TELLS YOU -- EVEN IF IT VIOLATES A PUBLISHED PROC.