Went to extremes

If you were to say, "went to the extreme," the natural question that would arise in the hearer would be, "which extreme?"
Saying, "went to extremes," is broader, and reflects the reality that, when one is pressed, one goes "to the extreme" in more than one way, so that, in sum, one goes to "extremes."

also "went to extremes" could mean a mutiple series of events that someone did something extreme. thus the plural! if you just said "went to the extreme", it could just be assumed that there was only one event in which the subject actually did something to the extreme. however, the plural version doesn't seem like it would be required when speaking of multiple events, as this phrase is really kind of colloquial afterall.

I tried to find a bit more about the origin of "went to extremes" by googling. When I linked to a page and found the following use of the phrase, I decided it was time to move on to something else.
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My Dear Spiritual Advisor,
As you instructed, I turned into an ice maiden every time my dear husband attempted to entice me into sinful relations involving non-Christian penetration. I was sure that my marriage was going to be saved and we would spend eternity blissfully singing together in Jehovah's choir, but I was seriously mistaken. My husband passed away in a freak accident involving a canister style vacuum cleaner and watermelons. Thank Jesus the church authorities have decided, since I am a pillar of the congregation, to keep the scandalous details of my late husband's satanic demise from the general public.

Now that I am back on the market I intend to screen my suitors very carefully and with your loving guidance. As a white woman, would it be wrong for me to date an African American? Roy is very attentive and caring, but I do not know if God approves of racially mixed marriages. We seem to be a perfect couple, but if Jesus disapproves, I will end this romance immediately.

Overcome with Jungle Fever,
The Widow Jackie

Dear Jackie,

The stories about black mens' endowments are all true. (However, Sister Rossetta hopes you have not learned this first hand.) Jesus knows that informed white women would never voluntarily marry white men over black men. For this reason, Jesus has commanded us to separate the races in marriage. If not for his proscription, the entire Caucasian race would eventually dwindle and die.

Earlier generations went to extremes with separate drinking fountains and buses to keep white women blissfully ignorant of the black stallion's lure. In today's racially mixed society, individuals must be stronger. However, the Bible Clearly States that God will not allow any temptation beyond your ability to resist.

Keep the faith, and keep a Bible between you and Roy at all times. 'cause "Once you go Black, you never go Back"

Sister Rossetta

could be more than 1 extreme. everything has an extreme could be more than one making it plural.