I love it when someone tries to show how knowledgeable they are by critiquing someones post. And then they contradict themself and show they didn't understand the concept highlighted in the post themself.That is what you do when setting the ignition later on.
The point of ignition inside the distributor is already set from factory, and can not be adjusted by turning the distributor.
The reason for a wider rotor is depending on ignition advance curve.
If you do not understand the post, go and look up the engine section in the manual. Particularly the instructions for setting the distributor/s position for all Motronic equipped Alfas.
Then think about it.