If you started the game at level two as 1 Trapper / 1 Counterfeit-mage+other archetype your trapper can't disarm magical traps - without the awkwardness of having been able to do so in the past and suddenly not after dipping in rogue of all classes :D
What if the replaced feature can be bought with a feat when the time comes.
Say a Oracle Community Guardian and Psychic Searcher, which only overlap on the Revelation gained at 3rd level. If the player locked the feat he gains at third level to go towards paying for the extra revelation feat, could he take both archetypes?
I'm looking for rules as written answers, but am curious about RAI, if there's evidence for it, such as a designer's comment.
I'd also appreciate a side-note based on GM experience as to the estimated threat to balance and whether you'd allow it.