Mmm, so one should ignore the degree of elbow flare and merely aim to get the bar to hit mid-chest (nipple line) and keep the elbows under the bar?
The thing is why then do people still have a pronounced / bar path if the initial position of the bar should already begin pretty much over the mid-chest, then wouldn't lowering the bar to a mid-chest position be a pretty much vertical straight up and down? If you can make a pronounced / bar path then you're either starting with the bar above your upper chest/neck region and then moving down to mid-chest, or you are beginning with the bar over the mid-chest but going down to a position on your lower chest.
Also i don't see how you can vary the degree of elbow flaring you make if you are keeping your elbows under the bar. The only way i can think of in allowing a person to make themselves change their amount of elbow flare while still having the elbows under the bar, is either by making your grip wider or narrower, or changing the position of the bar in your grip (which i don't think is optimal).
Please correct me.