It seems to me that there are more than one fit, for the same person.
Generally now an open hip angle is recommended.
1980s riders used the bunched up at the back very closed hip angle fit. Even in sprints Eddy Merx would be way way bunched up at the back with a very closed hip angle.. This fit allows for a quad (and even abs) push forwards, followed by a glute catapult.
Since the 1990s, however, permanently (to a degree) superman sprinting in "aero position", using quads became faster in people using drugs, and radios to facilitate a tight formation sprint relay. Most folks became too fat to use the bunched up at the back closed hip style anyway. This is a shame at least because as you get older, using your glutes is very important. Classic road bike fit was almost forgotten.
There is more than one fit.