LTSS WHEN DSNDING ACR X RECEIVES TCASII AND STOPS DSCNT AT SAME ALT OF ACR Y. RPTR HAD PROJECTED THE DSNDING ACFT TO BE AHEAD AND BELOW THE CONFLICTING TFC. OPERROR.

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ACR X ENRTE TO CMH DSNDING TO 11000 FT; STOPPED HIS DSCNT AT 16000 FT BECAUSE HE SAW TFC BELOW HIM ON TCASII. #2 ACFT WAS ACR Y WBOUND TO ROD VOR AND BEYOND. (JUST S OF V72). I WAS THE RADAR CTLR OF THE ROD (ROSEWOOD) SECTOR; LOW ALT; AT THE TIME OF THIS INCIDENT. THE SECTOR WAS MODERATELY BUSY OR BETTER WITH TFC (15 PLUS ACFT). 5 MINS PRIOR TO CONFLICT; ACR X STEPPED DOWN TO 17000 FT BECAUSE OF ACR Y AT 16000 FT. 2-3 MINS LATER UPON A SCAN OF HIS DSCNT PROGRESS; I CLRED ACR X TO 11000 FT. AT THIS TIME ACR X WAS AT ABOUT 19000 FT WHICH TOLD ME HE HAD A GOOD RATE OF DSCNT GOING WHICH WOULD ALLOW HIM TO VACATE 15000 FT PRIOR TO ACR Y'S AIRSPACE; ALSO; UPPER WINDS WERE FROM THE NW WHICH GAVE ACR X A GND SPD OF 510 KTS WHICH PROJECTED HIM TO BE AHEAD OF ACR Y'S PROJECTED POINT OF CONFLICT BY MORE THAN 5 MI. AT AROUND XX43 I OBSERVED THE CONFLICT ALERT BLINK; SEEING BOTH ACFT AT 16000 FT 4.75 MI APART. I TURNED ACR Y R 20 DEGS AND ASKED ACR X TO VERIFY HIS ALT BECAUSE MY ESTIMATE OF HIS PREVIOUS RATE SHOULD HAVE HAD HIM 14000 FT OR LOWER. ACR X SAID HE WAS AT 16000 FT BECAUSE TCASII HAD INDICATED TFC AND SO HE STOPPED DSNDING. I BELIEVE MY INITIAL ASSESSMENT OF HIS RATE GAVE ME TIME TO ISSUE HIS DSCNT TO 11000 FT. WHY HE SLOWED HIS RATE? HE DIDN'T ADVISE; HE DIDN'T SAY HE WAS LEVELING EITHER. THERE WAS NO WX OR CHOP. THE FREQ WAS BUSY BUT HAD HE CONTINUED AT EVEN 1500 FPM RATE; I THINK HE WOULD HAVE BEEN 1000 FT OR MORE BELOW THE TFC. HE; ACR X; SAID HAD I ISSUED TFC AHEAD OF TIME; WOULD HAVE HELPED AND I AGREE THIS COULD HAVE BEEN USEFUL BUT DUE TO TFC VOLUME I DIDN'T THIS TIME. IF DSCNT/CLB RATE; SPD CHANGE SIGNIFICANTLY WE SHOULD BE ADVISED.