A B737-300 CAPT RPTED THAT HE RECEIVED CONFLICTING INSTRUCTIONS FROM THE RDU LCL CTLR REGARDING HIS TKOF CLRNC WHICH CAUSED ANOTHER ACFT TO GO AROUND.

Narrative

TAXI OUT TO RWY 23R; RALEIGH-DURHAM; TWR INSTRUCTED US TO HOLD SHORT. WE REPLIED AND DID SO. ACFT ON A 3-4 MI FINAL. TWR ASKED IF WE COULD TAKE AN IMMEDIATE TKOF. WE REPLIED TO THE AFFIRMATIVE. TWR CLRED US FOR TKOF. WE RESPONDED. ABOUT THE TIME THE NOSEWHEEL CROSSED THE HOLD SHORT LINE; TWR INSTRUCTED US TO CANCEL TKOF CLRNC; HOLD SHORT OF RWY 23R. WE REPLIED THAT WE HAD ALREADY CROSSED THE HOLD SHORT LINE. TWR THEN CLRED US FOR IMMEDIATE TKOF. WE RESPONDED; 'CLR FOR TKOF.' AS WE WERE LINING UP WITH RWY CTRLINE; TWR INSTRUCTED US TO CANCEL TKOF CLRNC; POS AND HOLD. WE RESPONDED; 'POS AND HOLD.' WE HADN'T BEEN DOING MORE THAN 15 KTS GND SPD AT THIS POINT AND THE ENGS HADN'T BEEN SET FOR TKOF. I THINK THE TWR HAD SENT THE APCHING ACFT AROUND; BEING 200-300 FT FROM THE APCH END OF THE RWY NOW; AND HAVING HAD UP TO 5 CONFLICTING DIRECTIVES FROM THE TWR IN A SPAN OF LESS THAN 30 SECONDS. WE TOLD THE TWR WE NEEDED TO CLR THE RWY BEFORE BEGINNING ANOTHER TKOF ROLL. WE GOT CLRNC TO CLR THE RWY; DID SO AND TOOK OFF UNEVENTFULLY PERHAPS 2 MINS LATER. I THINK THE TWR CTLR JUST SECOND-GUESSED THIS DECISION TOO LATE INTO THE SIT.