Post-functionally slow

In Spook Country (2006), William Gibson talks about music, “though not in the old plays-a-physical-instrument-and/or-sings modality”:

“Inchmale understood it, though, and indeed had championed it, as soon as it was digitally possible pulling guitar lines out of obscure garage chestnuts and stretching them, like a mad jeweler elongating sturdy Victorian tableware into something insectile, post-functionally fragile, and neurologically dangerous.”