I have to say that's fairly stupid (I'm talking about the claim which the quote is making and generalizing over a whole population; I am not doing argumentum ad hominem here).

I've seen many sorts of (fascinated) mythical claims on how the Japanese think/communicate/have sex/you name it differently and they're all ... well, purely mythical. Even if I, for the purposes of this argument, assume that beoShaffer is right about his/her Japanese teacher (and not just imagining or bending traits into supporting his/her pre-defined belief), it's meaningless and does not validate the above claim. Just for the sake of illustration, the simplest explanation for such usages is some linguistic convention (which actually makes sense, since the page from which the quote is sourced is substantially talking about the Japanese Language).

Unless someone has some solid proof that it's actually related to thinking rather than some other social/linguistic convention, this is meaningless (and stupid).