Term for a technique intended to draw criticism to an opposing view by overstating that view as your own (often emphatically)

Solution 1:

I don't know if this is really what you're referring to, but there is a part of the Socratic method often referred to as "Socratic irony" where you attempt to expose the flaws of someone else's argument by initially agreeing with them with the express purpose of exaggerating them to underline their absurdity.

According to the article "Socratic irony" in The Oxford Dictionary of Philosophy (Simon Blackburn. Oxford University Press, 2008), a Socratic irony is "Socrates's irritating tendency to praise his hearers while undermining them, or to disparage his own superior abilities while manifesting them."

Solution 2:

A few of the other answers have mentioned irony but I'd like to add sarcasm more specifically.

Sarcasm is the use of words usually used to either mock or annoy someone, or for humorous purposes. Sarcasm may employ ambivalence, although it is not necessarily ironic. Most noticeable in spoken word, sarcasm is mainly distinguished by the inflection with which it is spoken and is largely context-dependent.

[Wikipedia]

I think the key is that the words are used to mock or annoy someone who 'is on the side of' the point of view which is ironically (and sarcastically) stated. If the words were spoken you might hear the sarcasm (tone of mockery) in the inflection, but that tone is lost in the written communication which, in some contexts, might make it difficult to discern if the speaker holds or opposes the point of view which is represented. This could lead to annoying people who are 'against' the point of view which is stated also. Annoying all parties might be a bonus for an especially sarcastic person!

Solution 3:

Assuming he's doing it to incite blowback on the people who actually hold the views he's pretending to espouse, he could be considered an agent provocateur carrying out a false flag operation.

From the Wikipedia link:

A false flag operation is an act committed with the intent of disguising the >actual source of responsibility and pinning blame on a second party.

Solution 4:

Sounds like satire and/or irony to me.

As I understand it, he is saying those things ironically.

Explicitly stating someone's position or reaction to something in a way that highlights its absurdity or hypocrisy is a type of criticism called satire. This is sometimes used to humorous effect.

While it may be framing it or phrasing it in such as way as to highlight its absurdity, it's not inherently dishonest in that it's essentially making the same argument as those whom he is criticizing were making, or not straying too far from what the original argument that is being criticized was saying. Sometimes this is done by making an analogous argument or by drawing parallels between the argument being criticized and some ad hoc fictitious argument being made in the critique.

If your friend is making a highly exaggerated form of the argument, or extending it beyond the intent of the person who originally made it, to the point of absurdity, and then your friend criticizes the result, that is argumentum ad absurdum.

If your friend is substantively altering the original argument and then is criticizing the substituted argument that is similar, perhaps superficially, but not in fact the same argument the party being criticized was making, well then that is a straw man argument/fallacy.

It is also possible your friend may have just been mocking someone or their position. Mocking, ridicule, or derision is different than irony. Irony is a statement that, when taken in context, may actually mean something different from, or the opposite of, what is written literally; the use of words expressing something other than their literal intention.