ZFW CTLR QUESTIONS HIS OWN ACTION WHEN PROVIDING A FLT ASSIST TO AN ACFT IN EMER SIT.

Narrative

THE MOONEY (9000 FT) WAS NBOUND OVERFLYING TO SPS; THE CESSNA (8000 FT) EBOUND TOWARD JEN. WHEN THE MOONEY WAS 3 OR 4 MI S OF THE CESSNA; HE INDICATED HE HAD AN ENG PROB AND WANTED TO LAND AT STEPHENVILLE. THIS REQUIRES THAT HE DSND VISUALLY THROUGH THE CESSNA OR BE VECTORED AWAY FOR STANDARD SEPARATION. THE ARPT WAS ONLY 10 MI AWAY AND THE CESSNA WAS BTWN HIM AND THE ARPT. THE WINDS WERE STRONG FROM THE N; SO HE WANTED TO SET UP FOR A N APCH. I CALLED THE TFC TWICE AND KEPT HIM LEVEL; HOPING HE WOULD SEE THE CESSNA. THEY WERE NEVER IN DANGER OF COLLIDING; BUT I FELT HE NEEDED ME TO GET HIM DOWN; SO HE COULD SET UP HIS APCH. I SORT OF DECLARED AN EMER FOR HIM AND I FELT TIME/DISTANCE WERE BECOMING CRITICAL. I DSNDED HIM AND IT ALL WORKED OUT FINE IN THE END. BUT THE ACFT SHOULD HAVE EITHER INDICATED HE WAS FINE TO BE MANEUVERED AT ALT FOR THE TFC; OR TAKEN HIS OWN DECISION TO DSND. I FELT TRAPPED BY THE RULES AND HE SHOULD HAVE BEEN MORE FORCEFUL IF HE NEEDED LOWER; OR BEEN MORE EXPLICIT THAT HE COULD WAIT FOR THE TFC.