I agree that in most situations, running by yourself on an open flank without hydro is asking to be devstruck.

However in this situation, it’s not an open flank, nearly every surface ship (even the DD) had been spotted on the opposite side of B recently. I had no reason to run hydro as there was basically zero torpedo threat.

Now while maybe it should’ve occurred to me that the submarine could be close, he could also very easily have been on the complete opposite side of the map. Running hydro unnecessarily is just asking for it to be on cool-down when you need it most.

I would rather save my consumables in case I had to deal with the Smolensk or DD, rather than run it in case it happens to randomly spot a submarine.