ALTDEV.

Narrative

UPON HDOF TO SECOND APCH CTL FACILITY; OUR FLT WAS CLRED TO MAINTAIN 4000 FT AND 190 KTS TILL THE MARKER. WE WERE ON A STEEP BASE APPROX 18-20 NM N OF THE ARPT WITH CONVERGING ACFT FROM ALL QUADRANTS BEING VECTORED BY APCH CTL FOR THE PM RECOVERY. ADDITIONAL INSTRUCTIONS WERE RECEIVED TO INTERCEPT FINAL APCH COURSE. AS PNF; I HAD RESPONDED TO TFC CALL WHICH WAS INTENDED FOR A DIFFERENT ACFT; 'MAINTAIN VISUAL SEPARATIONS FROM PARALLEL TFC'. SOME PREOCCUPATION WITH THIS CLOSE TFC APPARENTLY TOOK MY EYES 'OFF OF THE STORE' AS I RESPONDED TO APCH CTL ABOUT VISUAL SEPARATION. APCH CTL AND THE FOLLOW ON ACFT BEHIND US CORRECTLY SORTED OUT THE TFC RPT TO WHICH I ACKNOWLEDGED. MEANWHILE THE FO HAD INTERCEPTED THE GS AND STARTED DOWN THE CHUTE. AT 3600 FT; APCH REQUESTED IF WE HAD 'FIELD IN SIGHT.' WE RESPONDED AFFIRMATIVE. THE NEXT REQUEST WAS FOR OUR ALT. WE RESPONDED 3500 FT. AT THIS POINT WE WERE THEN CLRED FOR A VISUAL APCH. ALTHOUGH ABOVE/ON THE GS FOR THE PAST 3-4 NM; WE HAD NEVER BEEN CLRED FOR THE APCH OR CLRED VISUAL APCH. WORKLOAD FOR THIS PHASE WAS PARTICULARLY HVY DUE TO CONVERGING TFC; TFC CALLS AND APCH HDOFS. ADDITIONALLY; HAD WE CORRECTLY MAINTAINED OUR 4000 FT CLRNC; WE WOULD HAVE BEEN ABOVE/OFF SCALE THE GS. THIS TOO MAY HAVE PAINTED AN UNUSUAL DISTRACTING DEPICTION WHICH LED TO INCORRECTLY STARTING DOWN PREMATURELY. RECOMMEND MINIMUM HDOFS IN CONGESTED AIRSPACE.