I know for sure and you can check any good Latin etymology book that–
1) Teste/Testiculum (lit. “Witness/little witness”) The origin of the word would be obvious to anyone used to write or speak Latin. The “little witnesses” stand outside witnessing but not participating…(you know when) These Romans were funny… I know. But that is the origin of the word. From “teste” (“witness, in the sense proof”) More than one “testa” (teste) assents to a fact. From the lower Lat. plural for heads comes the word for witness, then pluralized again as testi or in the more common diminutive “testicullum”.
2) Atestare: (to assent) means “to nod”, “testa” being the word for “head”. To assent with your head, literally. From that root a number of other words come: “testamentum” (pact, accord, last will, contract)
Romans did not swear by their genitals but by their “lares” their family gods and ancestors.
I challenge anyone to find one serious historicla reference to the people of Latium swearing by holding their genitals (Italians today do it only when they are very angry at someone and not to swear to the truth of their statements, believe me)
Your comment is spurious etimologically and historically. Cheers

That reminds me of a very embarrassing conversation from my 2L year of law school about women in legal academia. The other student kept getting this quizical look, and at the time I wondered why.

I found out later. It turns out that I had wrongly assumed (from the name) that Cass Sunstein was a woman. (Well hey – I knew a woman named Cass, before law school!)

Oops.

And along these lines (sort of), it’s always uncomfortable when people start asking substantive questions about things you have a vague familiarity with, but don’t know anything about. Like real estate law, for example. So, if you’re buying a condo, don’t ask for free legal advice from your friend who does employment law. :)

My own similar Modern Jackass moment came when I was admitted against a professor’s better judgment into a graduate seminar while I was still an undergraduate. Upon reading a book by Eudora Welty, whom I knew very little about (She was southern), I made the mistake of determining she was African American based on a sepia-toned dim picture I’d seen on the dust-jacket of one of her books. Proud as can be of myself I worked out an argument for why reading the book through the lens of race in America illuminated key insights, because after all Welty was a black woman. The professor sat for a second stunned, and then burst my bubble, “Eudora Welty’s white.”
It was beyond awful.