"The power source for the belt system is the crankshaft. The crankshaft pulley directly pulls the A/C pulley, then the power steering pulley, then the water pump pulley, and then the alternator pulley. The remaining "loose" end is held by the belt tensioner system. So, I should think a seized or "hung" accessory should break the belt or slip, not pull the tensioner out"


I am not sure that I can agree with this. The belt is connected and if there is a resistance from one component, the tensioner mechanism will 'take it'. Means it will absorb the forces within its engineered spring/shock. The tensiner can stay at this exhaustive mode for a while until things back to normal. when these forces are more and the tensiner stays to its limits longer, it has no other way but to transfer these forces to its components or its holding base, the bolt. It might depend on which component is more effective on that, before or after the tensioner on the loop. That is what I think, at least for now, and it imight be better to check all the components to prevent similar event.