Not that I have a desire to do this, but could you, in theory, Multi-class with two mutually exclusive archetypes?
Say regular Bard and Magician Bard (Magician gets rid of inspire courage)
You CAN have two Archtypes I've heard... so long as they don't replace the same things.
I Don't have the page up right now, so I'm not sure if there are any bard ones that can do that... but I think there are a couple of Monk or Rangers that you can have two archtypes... but it's not.. (just throwing things out here...) Not, Level 1 Martial Artist, Level two Sensai.... It's Level three Martial Artist Sensei.
But yeah, taking any archtype shuts the door on the original base class.
RAW no. Although if I was the GM I would probably houserule that you can, because it isn't generally overpowered, unless it was something super cheesy.