Having thought about it for a bit, could you say that the 777 acts like a non FBW aircraft eg. 737 for pitch/power coupling?
IMHO absolutely not - it certainly doesn't act like the similarly under slung non FBW 747 - on that the first effect you notice if you applied a handful of power is that the nose pitches up immediately unless you do something about it, OTOH put power up on the 777 and there's absolutely no pitch up. It's only once you actually get the IAS increase that subsequently on both types there will then be a need to trim for any subsequent speed change.
Think back to what used to be taught by some
as "straight and level two"( power + attitude + trim and all that) on a single piston/jet, the triple from a handling POV really is that straightforward, assuming the FBW is in normal mode.