Reviving!
I'd argue that Extracts function as the spells they mimic and that this one ability, just adds that you can create variations. Its assumed that you follow the rest of the rules of the spells as normal much like how one applies an archetype.
Example: Synthesist Summoner summons Eidolon Armor...aside from wearing a translucent version of your eidolon, the ability functions just like the Normal Eidolon class feature....dictating that your Eidolon HAS to look pretty fantastic/amazing/otherwordly plus the matching symbol thing.
