William shakespeare's works contain nearly all the words in use in the English language except the derivative or the LOLs. Was he revered in his time. Naaa. There is no record as such. Today, No literary specialist can be called so if he cannot recite his sonnets and bisect their meaning.
Is writing like wine matured in wooden casks from wherein there comes a distinct color, texture, smell and taste which makes it more desirable. Why is listening to the same content of the book desirable by the author. Is it because we cannot rush through it or change pace. A recording can be paused but live talk, Not possible. Do we bisect and dissect talk as we do with the contents of a written material. No. We may do that with certain portion of it, But a written book can be dissected word to word.
The court of law depends more on the certified hard copy than the vocal certification. Talk tends to change over a period of time, though the body and format may remain the same. Playwrights try to accommodate as much recent tastes as possible in the same format and body. Macbeth, the original is still the same, but their renditions bring in spontaneity and current affairs, thereby adulterating the original(is it?). The standard does not change. Interpretation is simply talking about the original. There are as much renditions of the Bhagavad gita as the renderers.
A writeup can be concise as well as elaborate. Talk can be either or neither. Talk may drop a thing or two. The validity of the writeup depends on the time taken for the same and also on the iterations of the work before bringing out a copy. There area a lot of things conveyed with body language during a talk. A writeup dont have this luxury except when explicitly stated.
Talk can coerce the listener to think as per his perceptions but a writing is immune from this. The reader can perceive and fill up the blanks as needed to complete the picture. Are science, mathematics and legal writings the same as general writing. Are they not open for scrutiny, Are they not open for perceptions/improvements. Yes, they are. The are all iterations getting better. Departing from the general by every iteration.
Are we just obsessed with the written word than the spoken? Are we comfortable with holding a book rather than an audio or a video recording? Is the probability of finishing a written book more than an audio/visual? Is the printed two dimensional page capable of answering and explaining multiple dimension of space and perceptions.