(assigned review)  I re-read the whole text, and noticed nothing that I'd consider wrong or missing.  (I didn't review implementation section; except Knot's is basically my text.)

I think the current text is a quite nice reference for DNS fragmentation; I'm not aware of anything close.  IIRC I think the text has improved greatly over the years.

Nit which I've already posted somewhere: I don't expect the double thanks is intentional?  (not personal, Peter :-)