If the model cannot be tested, it is useless. If you are able to create the model, then you should be able to test it. That is not rocket science, it is common sense.

I strongly suspect that russian name for men genitalia was used. Russians can say a whole sentence, which of course is unprintable, using only this word :)

Not exactly. Half of the list are just ordinary words with negative meaning. Lithuanian really lacks strong swearwords of lithuanian origin. So we import the majority from russian, some from polish. But this does not mean that lithuanians swear in foreign language. Usually some description is combined with foreign swearwords to make a satisfactory expletive. The curious side effects of this is that lithuanians can understand perfectly russian swearing, but not vice versa, and that some really bad russian swearwords sometimes can pass just as a salty language. Sometimes I really envy other languages for having original swearwords, lithuanian ones for some reason vanished. I really doubt that they never existed.

beta=solve(t(x) %*% x) %*% t(x) %*% y,

NO, NO, NO!

beta=solve(crossprod(X,X),crossprod(X,y))

is much nicer, and it is less susceptible to round-of errors.

I think the usual rule is that, you must earn the benefit of the doubt. I think Russia never even tried to do that for a period longer than a blink of an eye.