Hi Denti, I had a feeling you might jump onto this
I guess overriding a soft derate by manually forwarding the thrust levers is obvious, but the interesting case would be a windshear encounter shortly after takeoff - when does the FMC cancel TO1/TO2 or rather what will double pushing TO/GA give you in this case?
Obviously we use performance analysis software (made originally by that big German holiday airline that had a bird on the tail once upon a time) for our takeoffs, it has a surprising talent to reduce 4000m runways to a mere 200 meters stop margin with a combination of low flap settings, improved climb and a ridiculous double derate
Sure, a derate will reduce VMCG and VMCA, hence the FCTM note that during an engine failure thrust should not be increased above the green FMC N1 target unless terrain contact is imminent (which might be either the fixed derate limit or the actual double derated takeoff limit as it is on your airplanes Denti
)...