I was originally going to poo-poo the very idea of using mines as torpedo decoys on purely technical grounds, saying nothing about the tactical lunacy of it all. However, i decided to do a little testing first, since I hadn't tried this since SC (the last time sombody brought up this ridiculous idea) and I wanted to make sure nothing had changed between SC and DW before I began ranting. NOTE: my testing was performed on STOCK DW, minus the LW/Ami mod.
- Active torpedo vs SLMM in transit: the active seeker will not detect the SLMM, and the torpedo will whizz right by it without detonating.
- Passive torpedo vs. SLMM in transit: the passive seeker tracks the SLMM, and the torpedo adjusts course to intercept and destroy the SLMM.
- Active torpedo vs. moored mine: The active torpedo will home on the mine and destroy it.
- Non-enabled torpedo vs. moored mine: the influence detonator will not trigger on a close-aboard torpedo in transit; see
image.
Bottom line... it's possible to use a mine as a decoy against passive torpedoes... but it's not likely that, as a submarine, you could lay enough mines as a defense against incoming torpedoes... not to mention the TIW generated for other players when you launch a SLMM...
Say no to SLMMs! (as decoys

)
TG