the whole of that Jacob's Optical Stairway album is great
re EZ Rollers, I was surprised how enjoyable the Weekend World album was hearing it for the first time earlier this year (whereas the actual EZ debut Dimensions of Sound i recall from the time of its release as being too clean, too mild - part of that disappointing queasy moment when Moving Shadow seemed to lose it, bongos a-ripplin' on every bleedin record)
yeah there's jazz in the sense of the add-on's, the superfluous flava elements - textures, pale-blue chords, light-touch pads, overall luxuriance to the arrangements etc
and then there's jazz in the sense of what's going on with the drums ie more fundamental structure, rhythmic grammar of the music
David Toop said something memorable (that i can't quite remember exactly!) about how the rhythmic structure of jungle was like 'dropping the bomb' in bebop - the bass-boom syncopating against the clatter of the drum kit, is how i took that
perhaps someone who knows anything at all about bebop can tell me if that's actually a valid analogy!