> But to _your perception_, it's politeness

That's not at all why Allen's comment is polite, and this is very much what I mean by "kindness requires no effort."

It's polite because it isn't actively negative towards the other person. That's all it takes. Redundancy is irrelevant.

Allen could've easily written:

> What you wrote makes no fucking sense and it's dumb as hell.

Which is both redundant and impolite.

> If you were my employee that needs softer language, I put in the redundancies.

Just to be redundant myself, redundancy is only loosely correlated with politeness. There are plenty of examples of terse, polite speech (and the inverse as well). You don't need to do this, and I would argue it's a hallmark of your particular writing style more than anything else.