I think we all agree that for 13 seconds my gear has to be up to the task. That means my power supply, my rig, the DC wiring mainly. If it can't do that at a minimum then the rest of the debate is moot. The next 15 seconds or so it rests and supposedly cools off. That is a concern as big as the previous one. Does it have adequate ventilation, etc? If that is compromised then the ambient temperature rise is going to begin accumulating. Most hams know that and provide adequate ventilation but I see pictures of so many shacks where the gear is all crammed together. Maybe they get away with it for a while but all bets are off. At that point Duty Cycle doesn't mean squat.