MD80 FLT CREW DEPARTS WITH 1 PACK MEL'ED INOP. FLT CREW USES PUBLISHED PROCS FOR 'PACK INOP' DURING TKOF; CLB. WORKING PACK BECOMES ERRATIC; FLT CREW DIVERTS.

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WE DEPARTED ZZZ1 WITH AN MEL. MEL FLT CREW OPERATING PROCS WERE FOLLOWED AND WE ELECTED TO DEPART USING OPTION #1 (TKOF WITH BOTH PACKS OFF). AFTER SLAT RETRACTION; R PACK WAS PLACED TO 'AUTO' WITH NO RESPONSE FROM PACK. AFTER APPROX 2 MINS; R PACK BEGAN OPERATING AND PRESSURIZING THE AIRPLANE. THE PACK WAS ERRATIC AND UNSTABLE FOR THE FIRST 5 MINS THAT IT DID OPERATE AFTER TKOF. QRH PROCS WERE FOLLOWED AND THE DECISION WAS MADE BTWN THE FLT CREW; DISPATCH AND MAINT CTL TO DIVERT TO ZZZ2. THE AIRPLANE NEVER CLBED ABOVE 8000 FT AND THE CABIN ALT NEVER EXCEEDED 6000 FT. AS SOON AS IT WAS APPARENT THAT WE WERE GOING TO MAKE A DIVERSION; WE EXTENDED FLAPS/SLATS; AS WELL AS THE LNDG GEAR IN AN EFFORT TO BURN AS MUCH FUEL AS POSSIBLE IN ORDER TO REDUCE THE LNDG WT BELOW 130000 LBS. AFTER CONSULTING WITH DISPATCH/MAINT CTL; WE WERE INFORMED THAT IT WOULD BE BEST TO MAKE AN OVERWT LNDG IF THE TIME TO BURN FUEL WAS GOING TO EXCEED 20 MINS. THEIR REASONING WAS THAT IT WOULD TAKE LONGER TO BURN THE EXCESS FUEL THAN IT WOULD TAKE FOR MAINT TO PERFORM AN OVERWT LNDG INSPECTION. WE LANDED UNEVENTFULLY IN ZZZ2 AND TAXIED IN TO THE GATE. WE ESTIMATE OUR LNDG WT TO HAVE BEEN APPROX 133700 LBS. AFTER A DEBRIEF WITH MAINT CTL; OUR DECISION TO USE OPTION #1 OF THE MEL FLT CREW OPERATING PROCS VERSUS OPTION #2 WAS QUESTIONED. AFTER RETURNING THE AIRPLANE TO ZZZ3 AND SPEAKING WITH MECHS AT THE ZZZ3 HANGAR; I'M NOT SO SURE THAT MAYBE WE SHOULD HAVE USED OPTION #2 OF THE MEL RATHER THAN OPTION #1 AS WE DID. MY ONLY COMMENT IS THAT MAYBE THE COMPANY SHOULD REWRITE THE MEL AND IN DOING SO CHANGE THE ORDER OF THE MEL FLT CREW OPERATING PROCS OPTIONS. IN ADDITION TO CHANGING THE ORDER OF THE CREW OPERATING PROCS OPTIONS; SOME EXPANDED WRITTEN GUIDANCE ON THE MEL PROCS MIGHT ALSO HELP MATTERS AS WELL.