The point loading on the head and tack of the sail is the same in both cases. However the point loading on the sheave, truck pin, line, masthead as a whole, and the mast are different for the two cases.

Perhaps you are confusing the luff tension load ("pull between two points") with the additional load put on the mast by the halyard fall. It is only this additional load that changes as you change the setup.

I don't think I can explain is any clearer than my last attempt. But I will wager, at 100:1 odds, that if you set up an experiment accurately simulating the situation, you will find I am right. It will be the easiest money I ever made, without the slightest risk.