|Balance (Photo credit: Wikipedia)|
As I see it, there are several ways this can fall out. Usually the reader learns something at the same time as the main character (MC). This makes sense because the MC is most often the point of view character. Also, the MC need to learn that something to move the story forward. And if you hold back too much from readers, they will become frustrated or bored and BAM! The book closes never to be opened again. But there are benefits to disturbing the status quo…
POV superior knowledge: when the POV character – especially an antagonist! – knows something that the reader doesn’t know (and the reader knows this), the reader will want to learn the secret and will read on for a while. How long depends in part on the genre and how often you have pulled this trick in the past and with how many other POV characters. This technique does not work well for close POV.
Temporary reader superior knowledge: the reader can learn something the MC is unaware of if you introduce the information during a different POV scene or an omnipotent passage (but those are tricky). Most times this technique is used to heighten tension and suspense because the MC is in more danger than he or she knows. This lets the MC be blindsided without sacrificing the logical flow of events. It is okay for an event to seem a bolt-from-the-blue to the MC so long as the reader knows the logic and cause of the event.
Long-term reader superior knowledge: Other times the MC never finds out everything the reader learns. If the MC doesn’t need to know, then why bore readers by repeating what they already know? This can be a useful way to tie-up loose ends that no longer affect the MC. And it can give the reader a sense of superiority.