christiaanJ
As an older fart and engineer used to running four far less powerful engines than either the Olympus or the CFM56 on ground runs, to retract the throttles from full power was an instinctive action if the aircraft moved, wall or no wall in front of the aircraft!
As to experience and youth, I suppose it can depend on who taught you in the first place. As an RAF Apprentice, there were hords of old boys in brown dust coats that droned on and on for hours followed, once on a squadron, or in this case, a manufacurers working party, more old farts in overalls. It certainly stopped me being cocky until I should have known better!
Today, the youth are not interested in listening whether you in a suit or overalls.