Here's an attempt for an answer drawing from credible and/or official sources. The best sources we have are the books themselves that create the Ngram in the question. If we click through to some of the results between 1898 and 1902 (for example), we can categorise them as follows:
Variation of goggle-eyed:
- "Gilded, gilded o'er, gilt edge on, glorious, google eyed, got a big head, got a bundle'jsgot a drop in the eye, got a smile on, got the gravel rash, greetin fou', groatable, groggy, gutter legged, guzzled. "
- "He was google-eyed and spiflicated."
- "Say, Mr. Pierce, couldn't you swipe that google-eye from Mrs. de Rutyer. She makes me so nervous when she points it at me that I feel like dropping."
- "On, say, drop dat google-eye, said Rade, in disgust."
- "Aha! And so you'd like to call my son after that google-eyed idiot you were engaged to before I met you !"
- "His tongue was much too large for his mouth, his legs were much too weak for his body, and his dull google-eyes stared and rolled like an idiot's."
- "It made him google-eyed and he walked off the Curb."
- "I'm sure that archers google-eyed"
- "Common Rock Bass ; Red-eye ; Google-eye" aka goggle-eye
Synonym for surf-scooter duck, aka goggle-nose:
- Popular synonyms: Surf Duck. Sea Duck. Horse-head Coot. Surf Coot. Google-nose. Gray Coot, etc."
- Popular synonyms: Surf Duck. Sea Duck. Horse-head Coot. Surf Coot. Google-nose. Gray Coot, etc."
- Popular synonyms: Surf Duck. Sea Duck. Horse-head Coot. Surf Coot. Google-nose. Gray Coot, etc."
Onomatopoeic gurgle noise:
- "He broke into a light Irish song, dancing the baby up and down until the little one bade fair to google itself out of breath."
- "A hurried visit to the cellar and the peculiar "google-google" sound led to a barrel which had been full of No. 1 Coach varnish"
Definite OCR error:
- "Goods manufactured."
- "Congleton"
- "1. O E. French, Lura Phillips, WF Chevalier, OE Klingeman, Carrie Coogle FE Buck, David Williams, ATS Owen,"
OCR is optical character recognition, the method of scanning pages and automatically attempting (not always successfully) to convert it to plain searchable text.
Unknown:
- "And vowed a most tremendous vow, By the great Google Tree,"
- "It 's right over yander at de head er de dreen — A-wish, wish, wishin' — Whar de branch runs google, an' de leaves is green— Des a-wishin'." Possibly nonsense/onomatopoeic from a child's lullaby.
- "It 's right over yander at de head er de dreen— A-wish, wish, wishin'— Whar de branch runs google, an' de leaves is green— Des a-wishin'."
- "Googie, George E" a soldier's surname, is it Googie or Google? Probably the same as the surnames below.
Unknown, Google Books image illegible, probably OCR error:
- "A. B "Google", John Carr, George Courtright", OCR error of a soldier's surname
- "OE KUngeman, Carrie Google. FE Buck, David Williams". Another surname.
- "Google Chas. W. Griffin Ivan Grimm Wm. F. Harris Krnest". Another surname.
- "FB Clayton, JP Google and others", OCR error of a surname
- "so they sit under the trees making merry over "google" and cake"
- "Googie, splendid color and markings, beat a nice housebred cat, not as clear or distinct in color." I think this says Googie and is the name of a cat in a list.
- "Not one of the pets Ever quarrels or scolds; They sleep and they wake And they crow and they coo And they talk in the language Of Google -goo-goo, (And they all take In Babyville there Are animals. too; tjaby kittens and bears". Probably nonsense word.
Unknown, no preview:
- Link
- Link
- Link, possibly OCR error from Matlese text
- Link
- Link
- Link
- Link
- Link
- Link
- Link
- Link
- Link, from a Spanish-English pronouncing dictionary
- Link
Summary:
- So the most common by far is google-eyed, a variation of goggle-eyed. The next is a variation of google-nose as a synonym for a duck that's also known goggle-nose.
- Next comes goggle as an onomatopoeic gurgle noise.
- There are some clear OCR errors (Goods, Congleton).
- There are quite a few surnames, at least one is an OCR error of the American Coogle, another could be Googie and I suspect the others were misspelling in American documents.
- Other uses appear to be either nonsense, onomatopoeic, made-up rhyming words or simply unknown.
Finally, although we didn't encounter them in this sample, the OCR often gets the published date wrong and a recent book about the Google search engine may appear in the results as if it were published in the early 1900s.
Like J.R., I don't see a good match between the language of the quoted sentence and any clear, recognized definition of churning.
The only definition of "churning away" that I'm familiar with carries a sense of purposeless activity; essentially it means "churning without a definite goal or foreseeable end," as in "He left the refrigerator door open, and the motor was just churning away all afternoon."
"Churning away" emphatically does not mean churning productively—not even at the impersonal, quota-driven level of "churning out," which, as Merriam-Webster's Eleventh Collegiate notes, involves "produc[ing] mechanically or copiously," but which frequently harbors an implication of poor or indifferent quality in the resulting output.
Making sense of the author's description of women churning away "dreams, fears, social [intrigues] and political intrigues" is complicated by the fact that one of the churned-away things (dreams) seems desirable, a second (fears) seems undesirable, and a third (intrigues) may be desirable or undesirable. Under the circumstances, it's hard to tell whether the women intend the churning to produce these things—or indeed whether the women have any clear intention at all with regard to their churning.
Maybe the author chose "churning away" to avoid the unflattering implications of "churning out." If so, I think it was a bad decision, since "churning away" does an exceedingly poor job of conveying what (I suspect) the author means. I would have suggested ending the sentence as follows:
...where the women of the home give voice to dreams and fears, and where elaborate social and political intrigues play out."
An author determined to tie the sentence to a kitchen-friendly verb could have used "cook up" or "brew up." Both have weaknesses of their own—"cook up" suggests fabrication of a deceptive kind, and "brew up" has witchy connotations—but at least they aren't borderline nonsensical, as "churn away" is.
Best Answer
I was able to find a few instances of computer and car products being described as brutal:
one here:
and another here:
I'll point out that I had to wade through some irrelevant content (much of it using brutal with a negative connotation) in order to find these. You will also notice that these examples are not from major marketing campaigns. I also searched YouTube for "brutal performance" and got lots of hits for loud cars (most of the results were for rock music videos).
The intended meaning of brutal in these instances is probably some combination of strong and rugged, or perhaps even manly or interested more in power than the feelings of others. How it is actually interpreted will vary from person to person, but some people will probably receive a negative feeling from the word (I am reminded of a list of adjectives in Hobbes' Leviathan, "solitary, poor, nasty, brutish, and short").
As for whether it is okay to use the word in marketing, that all depends on the image that you want to put forward. Sometimes a company is okay with being seen as focused on raw power rather than on other positive attributes (perhaps to attract customers who think, "I don't care if my engine is quiet, as long as it's fast!") In that case, I would say brutal is just fine to use.
Other words (possibly with different connotations) that might appear in similar marketing outlets are: