No need to make such an assumption. This matter differs from creationism/ID because in this matter we actually have hard evidence of a composer.
As soon as you take such evidence that DOES point to a composer and claim that must be the answer, then you are violating the premise from the onset that no composer be used to explain the origin of the piece.
Then you will be subjected to a lot of alternate arguments and how unscientific you are being.
The author (who exists outside of our time domain as proven by His knowing history before it happens) of the Old Testament became a man in Jesus Christ. He preformed many miracles before multitudes, including His own resurrection from the dead; which changed mankind to it's core.
Modern brilliant minds feel they can remain ignorant of the Holy Scriptures. This has not always been the case, as one need only look to the innovators of modern science to realize the truth.
Modern scientists have become to specialized to be called arbiters of truth. Evolutionary theory has demonstrably turned off their minds.
Jesus Christ, being God, is the source of all wisdom. Applying knowledge separate from Him is erroneous by definition.
Isa 57:15 For thus saith the high and lofty One that inhabiteth eternity, whose name [is] Holy; I dwell in the high and holy [place], with him also [that is] of a contrite and humble spirit, to revive the spirit of the humble, and to revive the heart of the contrite ones.
Dan 2:20 Daniel answered and said, Blessed be the name of God for ever and ever: for wisdom and might are his: