I'd held instrument ratings for years in single engine fixed wing and helicopters and thought I knew a fair bit about things, but it took a posting to Caribous to smarten my thinking up about the 'you're on your own' style limbo-land that is the IFR uncontrolled aerodrome departure in something that's often lucky to make 100 fpm with an engine out.
Not only that, but the other side of the coin which is what to do when you've left LSALT or MSA on an instrument approach and can't make the missed approach gradient with an engine out.
The blanket statement that you're responsible for terrain clearance on departure until established at or above LSALT is, well, a blanket, and hidden below its bland surface is a massive can of worms! Mixing metaphors there, but yes, the poor old IFR light twin driver has one of the trickiest jobs when it comes to discharging his or her responsibilities about missing the ground.