entertaining the possibility that “SWORD” = “WORDS”, and that as per Some Words on Openbound our Lord English is the embodiment of language, Caledfwlch being one of English’s key weaknesses suggests that one of language’s weaknesses is the power of language itself. this aligns with the more literal interpretation that the sword is made of a cueball, and that the cueball comes from the immortality clock, essentially making Caledfwlch a piece of the very workings of time that English protects himself with (alluded to by the use of the sword as the hand of a clock when Dave uses his powers in Collide).

(regarding malo’s toying with the idea of certain swords representing slurs in the former post, it struck me that English’s own name, Caliborn - itself the name of a sword - is treated as a dirty word by his adversaries, who censor it when they can’t avoid saying it; and that Caledfwlch essential hides Caliborn’s name within its own name, censoring the English name with the Welsh name?)

also pertinent is that Caledfwlch’s design owes its inspiration to Problem Sleuth’s Tectrixcalibur, a legendary sword that literally doubles as a writing implement; and specifically the writing implement of an Arbiter, especially for the purpose of ratifying the Law. again, as per Words on Openbound, time and/or language are the Law that governs reality; the legendary sword Excalibur, or Tectrixcalibur, or Caledfwlch, is a tool of the very Law that English represents.