LACK OF PROPER CREW COORDN, INCLUDING VIRTUAL REVERSAL OF ROLES BY THE DC-9 PLTS, WHICH LED TO THEIR FAILURE TO STOP TAXIING & ALERT GND CTLR OF THEIR POSITIONAL UNCERTAINTY IN A TIMELY MANNER BFR & AFTER INTRUDING ONTO THE ACTIVE RWY. CONTRIBUING TO CAUSE OF ACDNT WERE (1) DEFICIENCIES IN ATC SVCS PROVIDED BY DETROIT TWR, INCLUDING FAILURE OF GND CTLR TO TAKE TIMELY ACTN TO ALERT LCL CTLR TO PSBL RWY INCURSION, INADQT VIS OBS, FAILURE TO USE PROGRESSIVE TAXI INSTRNS IN LOW-VIS CONDS, & ISSUANCE OF INAPPROPRIATE & CONFUSING TAXI INSTRNS COMPOUNDED BY INADQ BACKUP SUPERVISION FOR LEVEL OF EXPERIENCE OF STAFF ON DUTY; (2) DEFICIENCIES IN SURFACE MARKINGS, SIGNAGE & LGTG AT ARPT & FAILURE OF FAA SURVEILLANCE TO DETECT OR CORRECT ANY OF THESE DEFICIENCIES; (3) FAILURE OF NORTHWEST AIRLINES TO PROVIDE ADQT COCKPIT RESOURCE MAN- AGEMENT TRNG TO LINE AIRCREWS. CONTRIBUTING TO FATALITIES WAS INOPERABILITY OF DC-9 INTERNAL TAILCONE RLS MECHANISM. CONTRIBUTING TO NUMBER & SEVERITY OF INJURIES WAS FAILURE OF CREW OF DC-9 TO PROPERLY EXECUTE THE PSGR EVACUATION.