I don't want to beat a dead horse re an intercept attempt, but if you think out of the box a bit, I believe it could have been ascertained whether or not the plane was being actively piloted. Why couldn't a fighter scare the crap out of someone flying the 777 just to make him move the stick a bit...you would know if it was on AP or not. I'm sure there would have been ways to know the condition of that aircraft.