Everyone says the more the better. Read 10 books a day. Read 20.

But, isn't there a limit on how much information one can process/assimilate a day/week? What if one can assimilate 5 books and the other 5 (or 15) are just waste of time? Is it possible to exhaust oneself with too much information. I mean, if you read 20 different books each day...I know subconscious is fast but is it that fast? Can it get clogged with too much PRing so other activities suffer?