By Tom Lanham
Updated December 11, 1998 at 05:00 AM EST

It was always a weird arrangement — guitarist Martin Gore penning gothic synth-pop dirges for Dave Gahan to moan/intone, while Gahan’s personal life grew as tortured as his Svengali’s grim outlook. But suffering doesn’t always result in great art, as Depeche Mode’s so-so anthology, The Singles 86-98, attests. The Gore/Gahan combo hasn’t worked since Music for the Masses, which is exactly where this set begins its 21-track downward spiral. C-