For example... learning a song on the piano. The only way for me to truly play a song well is to memorize it so that the feeling of every little movement of my fingers becomes a subconscious sequence. And the way I play the song is to just initiate the sequence and then let my subconscious take over. This is further evidenced by the fact that if I concentrate too hard on a song I'm playing from memory, I'll totally lose my place.
Cooking was probably a bad example... I'm not sure if I can explain it very well. But it has to do with something like how I always do something the same way because I know it works... and if I try something different, that's my conscious coming in, and it usually wrecks it...
With reading it's almost the same as playing the piano, except it has nothing to do with memorization. In order for me to be able to read something, two things need to happen. First, the text needs to develop in me a sincere interest in continuing to read it. I can't force myself to read something I'm not interested in. Second, I need to let my subconscious do most of the processing. If I'm thinking too much about how fast I'm reading or what the words look like or it suddenly feels less like I'm taking in thoughts and more like I'm scanning a page of letters, I won't comprehend anything my eyes are passing over.
It's almost like I have an outer brain and an inner brain I guess. The inner brain does all the important stuff like controlling my actions, but the outer brain needs to tell it what to do at a more macroscopic level, and it doesn't have a very good line of communication open to work with.
Maybe someone sliced the two halfs of my brain apart as a child. :)