I would counter that I'm not asking "How would my character act?" I'm asking "What does my character's particular set of skills mean they know?" Then, and only then, can I tell you what my character would do.
Honestly I, get where your coming from with justification, but how long will it be before you get tired of hearing "Well, my character reads a lot. You probably remember that I often mention going to libraries and booksellers once more pressing party business has been attended to and read them when I'm on watch or waiting around for any number of reasons. You may also recall that I said I was going to sit up for awhile talking with the woodsman when we stopped at his cabin for the night and he may have mentioned something pertinent." five times a session?
Personally, I recommend keeping track of character's Knowledge skills just like many DMs do with Spot, Listen or Perception. Then you can add bits yourself in the initial description adding that this or that bit of insight is the result of so and so's Knowledge Arcana or what's her face's keen eyes.