Pinkman,
You say:
"is there concievably a flight mode or condition such that when one engine unexpectedly loses power (eg if fuel feed blocked by a red plastic scraper) the other engine is electronically limited to avoid... well you tell me."
The answer to this is a NO!
Such a feature does not make any sense - imagine what would happen in a takeoff with one engine failing!
Whether the engines on the 777 are digitally connected, I do not know .
I have flown B767 and A340, and these aircraft types have digital connections between their engines.