WDB FLC FLIES SID WHEN CLRED RWY HDG. CTLR CATCHES ERROR.

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THIS IS A CLASSIC CASE OF 'FAMILIARITY BREEDS CONTEMPT' OR 'COMPLACENCY.' IN 25 PLUS YRS EVERY LGA RWY 13 DEP I HAVE FLOWN HAS BEEN EITHER A WHITESTONE OR A MASPETH CLB. I HAVE NEVER FLOWN A STRAIGHT-OUT RWY HDG; ALTHOUGH I KNEW IT EXISTED. BOTH THE WHITESTONE AND MASPETH BEGIN WITH A 175 DEG HDG ( IT USED TO BE 170 DEG) AND EITHER A L TURN TO FOLLOW THE WHITESTONE PROC OR A R TURN FOR THE MASPETH; DEPENDING UPON TFC FLOW. BOTH FO AND I HEARD A L TURN TO 050 DEG AFTER THE INITIAL HDG. I BRIEFED IT THAT WAY AND WE FLEW IT THAT WAY -- WHAT I MISSED WAS 'RWY HDG' AND FOUND THAT OUT WHEN CONTACTING DEP CTL. THEY ASKED US ABOUT OUR INITIAL HDG AND I CAME BACK '175 DEGS.' 'OH; YOU'RE DOING THE WHITESTONE CLB -- THAT'S NOT THE WAY YOU WERE CLRED -- WEREN'T YOU CLRED RWY HDG??' AFTER BEING TOLD TO CONTINUE OUR L TURN AND AFTER CLEANUP AND SUBSEQUENT CLB; FO AND I BEGAN ANALYZING THAT TURN OF EVENTS. WE FOUND OUT: YES OUR AIRWAYS CLRNC STATED 'RWY HDG.' AFTER TKOF THAT WE HAD ACKNOWLEDGED IT; FLT ENGINEER VAGUELY REMEMBERED HEARING IT ON TKOF. I CERTAINLY DIDN'T -- I WASN'T PROGRAMMED FOR IT!! I HEARD WHAT I WANTED AND EXPECTED TO HEAR. ALSO; IN RETROSPECT; THERE IS A COROLLARY HERE -- AND I CAN'T; AT THIS POINT; REMEMBER -- I KNOW I'VE BEEN CAUGHT BEFORE ON IT. IF THE TWR ISSUES A TKOF AND THEN MODIFIES (I.E.; ISSUES A HDG CHANGE AFTER THE CLRNC; I HAVE OCCASIONALLY MISSED IT. IF; HOWEVER; WE MODIFY THE DEP BEFORE ISSUING THE TKOF CLRNC; I MAINTAIN THERE'S A GREATER CHANCE OF 'HEARING' IT I.E. -- YOU ARE LESS LIKELY TO BE CAUGHT UP IN ENG SPOOL-UP; BRAKE RELEASE; LNDG LIGHTS; CHKLIST COMPLETION 'DISTRS.'