Both "written word" and "spoken word" make us human.  They make us unique; they have been in existence for centuries.  Different generations across the world speaking different languages to one another, all in the spirit of being heard and understood.  Indeed, language researchers such as Stephen Krashen (1976), amongst others, have created a compelling argument that understanding (comprehension) of language inputs of that language is effectively the only way to develop fluency in it.  A child proceeses language from his caretaker for hundreds of hours before they begin speaking, and in a limited capacity, and later spend thousands of hours of comprehension before formulating independent thoughts and responses.  To we expect that because we are adults, we can somehow accelerate this process?