Bake all maps at once or normal first then the rest?

[lookdev]

This guy says first the normal, there may be issues with masking later if all at once, can you please help understand? here is the exact time in the video:
https://youtu.be/boEzloMvBNU?t=521

[CAGameDEV]

This guy says first the normal, there may be issues with masking later if all at once, can you please help understand? here is the exact time in the video:
https://youtu.be/boEzloMvBNU?t=521

I only know about the Color IDs and if you bake with AA turned on it no longer leaves a solid single color and will cause issues when you use it to mask out your materials.