As an academic critic, it's my sacred duty to make arcane references and to be generally oblique. My scholastic background is in art history, and I'd say Brook uses the guitar like a great impressionist would a paintbrush. Brook doesn't muck around with dense pointillist soundscapes, or mere slapdash abstractions. Rather, he dazzles with an array of broad, measured strokes. He also revels in taut melodic understatement.
Brook seems to pore fastidiously over each picked note, shaping it to near- perfect ends.
In this sense, Brian and Roger Eno, guest musicians on Cobalt Blue are ideal collaborators for Brook. Although sometimes I think Roger's just a dispensable beneficiary of nepotism. I think he plays the triangle, and fetches the tea and scones or something. Well, of course. His attention to silence and restraint approaches that of players like Frisell and U2's the Edge.