Usage and Grammar
Q. The following parenthetical sentence was in the introduction relating to your 20th anniversary in the February Style Q&A: “Note that some styles have shifted slightly since then.” What is your view of not using the word that in cases similar to your sentence? The word that can be deleted without changing the meaning, or in my view, without making the meaning harder to understand. It can be deleted from almost every use when it follows a verb. Would you agree adding a comma after Note and then deleting that would be clear to the reader?
A. When there really is no chance of confusion, by all means leave out that. Otherwise, let it do its honest work. That is often needed to prevent reading the next noun as a direct object. For instance, “Note those styles” is a complete imperative sentence. A reader would reasonably believe styles to be the object of Note and not expect it to have a verb of its own—only to find that styles is the subject of the verb have shifted in the dependent clause. The reader stumbles. Newspapers notoriously leave out that, causing goofy misdirection:
“But the obtained records reveal the scope of visitor misbehavior is huge” (Matthew Brown, “Visitor Misbehavior Abounds at U.S. Parks,” Chicago Tribune, August 31, 2016, Kindle edition).
As for using a comma after Note, a colon would be better, and in fact is quite common in place of that (Note: Some styles have shifted). Note, of course, that the need for a comma or colon suggests that the omission of that would be problematic otherwise.