PLT OF AN SMA SEL TOOK OFF WITHOUT CLRNC DUE TO DISTR OF THE ROUTING OF PREVIOUS STOP-AND-GO LNDGS AND TKOFS.

Narrative

WHILE BUILDING NIGHT PROFICIENCY; I ENTERED SGR AIRSPACE FROM N (IWS ARPT). I WAS CLRED FOR A STOP-AND-GO LNDG (TOUCH-AND-GOES NOT ALLOWED AT NIGHT AT SGR). I HAD COMPLETED 1 LNDG AND WAS ON DOWNWIND FOR SECOND STOP-AND- GO. I WAS TOLD TO EXPEDITE LNDG DUE TO TFC WHICH WAS ON MISSED APCH FOR THE ILS RWY 35. I LANDED LONG; WHICH CAUSED ME TO STOP 3/4 OF THE WAY DOWN THE 5000 FT USABLE LENGTH OF THE RWY. I DECIDED TO ERR ON THE SIDE OF CAUTION AND ASKED TWR'S PERMISSION TO TAXI BACK TO THE ACTIVE. PERMISSION WAS GRANTED. WHILE TAXIING BACK TO APCH END OF RWY 35; TWR SUGGESTED DEP AT TXWY B WHICH WOULD PROVIDE PLENTY OF RWY. I RESPONDED THAT I WOULD ACCEPT THE 'B DEP.' I TAXIED ONTO THE RWY AND DEPARTED FOR MY NEXT CIRCUIT. WHILE CLBING OUT; THE TWR CTLR SUGGESTED THAT IN THE FUTURE I MIGHT WAIT FOR A TKOF CLRNC. I APOLOGIZED; AND STATED THAT I HAD MISUNDERSTOOD HIS SUGGESTION AS A CLRNC. HE STATED THAT SINCE NO OTHER ACFT WERE LNDG; NO HARM WAS DONE. I FEEL THAT I ERRED IN SEVERAL RESPECTS. SINCE I HAD BEEN CLRED SEVERAL TIMES FOR STOP-AND-GOES; I ASSUMED THAT THE CTLR'S SUGGESTION OF DEP FROM THE INTXN WAS A TKOF CLRNC. ALSO; MY USE OF NONSTANDARD PHRASEOLOGY; 'B DEP' PROBABLY ADDED CONFUSION TO THE SIT. I TOOK THE CTLR'S LACK OF RESPONSE TO MY ACKNOWLEDGEMENT AS A CLRNC ONTO THE ACTIVE (A DUMB ASSUMPTION). IN THE FUTURE; I WILL NOT ASSUME THAT THE LACK OF A CLRNC (OR RESPONSE) CONSTITUTES A CLRNC!