Otherwise serious Torah scholars in Yeshiva fear even speaking like a normal person when studying certain Sugyos in Shas. When learning Nedarim, or Shevuos, they will never use the first person point of view in an example, as though this would obligate them to do or avoid doing something…
It’s one thing to be superstitious in a religiously permitted way, such as not demonstrating Shechita on himself, not writing “Siman שמ”ד”, or being careful, as Sefer Chassidim says, around Iyun study of Moed Katan or Yevamos.
It’s one thing to avoid saying Birkas Hashem and the like, but quite another to mix in ridiculous “Yiras Shamayim”, as though reading the Talmudic words “I owe you a Maneh” (money) means you do, “Hareini Nazir” (I accept the Nazirite vow) demands nervous hedges תוך כדי דיבור, even “Harei At mekudeshes” (Behold you are my wife) are words to be avoided (maybe a female will pass within earshot of the study session!) [‘וגדולה מזו ש”ע אה”ע סימן ל”ה ט].
An otherwise rational person once said the Yiddish word for Yes should not be ethnically pronounced as “Yah”, for fear of uttering the Name in vain (יה)…
To psychologize, I think this is caused by repressed zeal for actual Halachos. Jews have a religious impulse, especially when generally cultivated, and if suppressed, it will express itself in insanity.