The first usage I see of "SIP" after the title is in parenthesis after the full phrase.

Yes, but halfway through the article. It is a mystery until then.

Isn't that standard in both APA and MLA?

Sorry — I don't know what those acronyms mean. I assume they're writing style guides? (Associated Press.. Acronym? Metropolitan Literature... Acronym?)

Also, is this an example of irony?

> Sorry — I don't know what those acronyms mean. I assume they're writing style guides?

Yes, the guides from American Psychological Association (APA) and Modern Language Association (MLA)

They are both the main results that appear when you google the acronyms and are quite common acronyms.

I am surprised you aren't familiar; I would expect that anyone who graduated from the US (United States of America) school system in the past 20 years would have heard of them. Are you not from the US?

Regardless of the style guides, it’s in the title and not explained until late in the post. The author should have explained or at least expanded the acronym in the lede