An unqualified section reference in this title means the tax code
What the document says“Except as otherwise expressly provided, whenever in this title, an amendment or repeal is expressed in terms of an amendment to, or repeal of, a section or other provision, the reference shall be considered to be made to a section or other provision of the Internal Revenue Code of 1986.”
The section provides that unless it is expressly said otherwise, an amendment or repeal expressed in this title as an amendment to or repeal of a section or other provision is a reference to a section or other provision of the Internal Revenue Code of 1986.
What the document actually says“Except as otherwise expressly provided, whenever in this title, an amendment or repeal is expressed in terms of an amendment to, or repeal of, a section or other provision, the reference shall be considered to be made to a section or other provision of the Internal Revenue Code of 1986.”
When this title names a section on its own, it means the tax code. That holds unless the text says otherwise.
The tax code is the Internal Revenue Code of 1986. So a bare section number in this title points there. That saves naming it each time.
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