In Detective Comics #600, when Batman celebrated his 50th anniversary, Jeanette Kahn (then Editor in Chief at DC) revealed that she initiated the yellow oval on the chest. I take her word for it.
And it was removed when she retired. Either to celebrate her passing the torch, or to bring Batman back to a more classic look to Batman. Remember, the test tube belt was replaced with the traditional belt with pouches.
Also, Frank Miller has no preference from what I can tell. In the Dark Knight Returns, Batman states he wears the yellow target to draw fire towards it because he can armor his chest, and not his head.
Once ruined by a gun shot, Batman uses the older outfit a brief time, until he switches to the armored look for the Superman fight.
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