The chord figures don't necessarily lack a third, but they do tend work against a drone(but not in every tune), that is either one big fat bottom note or the bottom note and its fifth--more or less what you'd get playing open tunings, though you can get the same effect using moveable chord positions in regular tuning--

The music is simple, in the sense that each voice tends to play a short repeating pattern that doesn't develop or change--but complicated in the sense that it is polyrhymic, meaning that voice has it's own rhythmic pattern, so that the ear hears the interaction between the parts, rather than the discreet parts.

The trick of playing the music is really in getting the feel of the rhythms--when you have that, everything else is just a matter of picking out which voice does what--

I am particularly fond of "Satellite", which sounds really complex, but becomes really clear when you figure out the rhythm--