A COMMUTER ACFT TAXIED ONTO THE ACTIVE RWY THINKING THEY HAD A TKOF CLRNC. ONCE ON THE RWY THE FLC HAD SECOND THOUGHTS AND RECONFIRMED THEIR TKOF CLRNC WITH THE TWR AND WERE TOLD TO TKOF OR CLR THE RWY. RPTR THINKS HE'LL DOUBLECHK WITH THE TWR PRIOR TO ENTERING THE RWY IF THIS HAPPENS AGAIN.

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WHILE PROCEEDING TO RWY 36L WE REALIZED THAT WE NEEDED A REVISION TO OUR FLT PLAN. REACHING THE HOLDING POINT OF RWY 36L WE ADVISED TWR THAT WE NEEDED TO READJUST OUR FLT PLAN WITH CLRNC DELIVERY REQUIRING APPROX 2 MINS. AFTER THE FLT PLAN ADJUSTMENT WE ADVISED TWR THAT WE WERE READY FOR DEP. AT THIS TIME IT WAS NOTED THAT THERE WAS AN ACFT ON APPROX THREE AND A HALF MI FINAL. WE ALSO OBSERVED THAT WE WERE THE ONLY ACFT AT THE DEP END OF RWY 36L. TWR THEN MADE A XMISSION OF WHICH THE FIRST PART WAS BLOCKED; THE SECOND PART READ 'RWY 36L CLRED FOR TKOF.' AGAIN NOTING WE WERE THE ONLY ACFT AT RWY 36L WE THEN RESPONDED 'ROGER FLT XYZ CLRED FOR TKOF.' WE THEN PROCEEDED TO TAKE THE RWY FOR IMMEDIATE DEP. AT THIS TIME MY COPLT SUGGESTED THAT WE RECONFIRM OUR CLRNC FOR TKOF; I AGREED TO HIS SUGGESTION. HE THEN SAID 'TWR RECONFIRM FLT XYZ CLRED FOR TKOF.' TWR THEN INFORMED: 'FLT XYZ CLRED FOR IMMEDIATE TKOF OR CLR THE RWY IMMEDIATELY.' WE THEN MADE A NORMAL TKOF WITHOUT INCIDENT. IN RETROSPECT IT MAY HAVE BEEN BETTER TO REFUSE THE TKOF CLRNC UNTIL AFTER THE APCHING ACFT HAD ALREADY LANDED. IN THE FUTURE THIS WILL BE MY COURSE OF ACTION.