007,
Just meant that you should tell ATC if the engine fails, via the normal calls.
Nobody will care about noise in the engine failure case, unless you make lots by crashing so please avoid that. Climb gradients to meet ATC requirements I believe become null and void, as ATC will probably get everything out of your way anyway so no issue there. And how long will you remain on the sid, or will an emergency turn/EO Sid take over? In which case, the min climb gradient no longer applies as you aren't conforming to the sid.
Trust me, it's the last thing you will be criticised for if you bring your craft home safely after an engine failure...