A B737-700 ON A PARALLEL APCH TO DEN RWY 16R BESIDE AN ACFT ON RWY 16; RECEIVED A TCAS TA THEN AN RA BELOW 2000 FT. THE RPTR QUESTIONS WHY XPONDER TA IS NOT SELECTED AT DEN.

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WE WERE ABOUT 6 MI OUT ON FINAL TO DEN RWY 16R AND HAVE BEEN CLRED FOR THE VISUAL APCH AND HANDED OVER TO TWR. WE WERE ESTABLISHED ON FINAL; ON GLIDEPATH; AND BEGIN FINAL CONFIGNS FOR LNDG WHEN TWR CLRED US TO LAND ON RWY 16R. ON RWY 16L THERE WERE 2 ACFT ALSO MAKING VISUAL APCHS. THE FIRST IS MI AHEAD OF US AND IS ABOUT TO TOUCH DOWN. I'M WATCHING THE TRAIL ACFT AS HE IS BEHIND US YET STILL CLEAN AND GAINING ON US. HE PULLS UP ABEAM US ON HIS FINAL PLACING US IN A SPREAD FORMATION. AS THE ACFT THAT I'M WATCHING PULLS ABEAM US; WE GET A TA ON HIM FOLLOWED BY A 'REDUCE DSCNT' RA THEN A 'CLB' RA. WE COMPLY WITH THE RA AND THEN RESUME THE LAST FEW MI OF OUR VISUAL APCH. IN CLOSE THEN WE GET ANOTHER RA ON THIS SAME ACFT INSTRUCTING US TO DSND. I SELECT TA ON THE IFF AND WE LAND ON RWY 16R IN SPREAD WITH THE ACFT ON RWY 16L. THE OTHER ACFT MADE NO MOVES OFF HIS FINAL OR GLIDE PATH DURING THE VISUAL APCHS. DEN'S TAILORED CHART POINTS OUT THAT WE WILL RECEIVE TA'S AND RA'S WITHIN THESE PARAMETERS BECAUSE RWYS 16L AND 16R ARE ONLY 2500 FT APART. THE TAILORED CHART DOES NOT; HOWEVER; PROVIDE GUIDANCE AS TO DE-SELECTING TA/RA IN THIS SCENARIO AS SOME SCENARIOS CALL FOR WITHIN OUR QRH. THERE WAS NO THREAT TO OUR OP IN THIS SCENARIO. WE COMPLIED WITH THE FIRST CLB AND THE NEXT DSND INSTRUCTIONS. FORTUNATELY WE WERE IN A POS IN THAT WE COULD SAFELY CONTINUE OUR APCH TO LAND. OTHERWISE; PER OUR MANUAL WE WOULD HAVE BEEN FORCED TO GO AROUND. THE POINT OF THIS RPT IS THIS: IF WE KNOW THIS SCENARIO WILL PRODUCE RA'S (DEN'S TAILORED CHART) WHY DO WE NOT ALLOW SOME RELIEF IN OUR PROCS BY DESELECTING THE TA/RA MODE IN THIS SCENARIO TO AVOID THE ISSUE ALTOGETHER? THE ACFT ON FINAL TO RWY 16L HAD TO BE GETTING THE SAME CONFLICTS; YET THEIR ACFT DID NOT MOVE ONE BIT OFF THEIR FINAL OR GLIDEPATH.