Well obviously this is the breakout recording of modal pieces, that is well-known - the album is a sine qua non of ECM . The question is whether the musicians, who are unaccustomed to it, really manage to keep it interesting, and whether they find ways to maintain the tension which modalism was designed to slacken. The idea I think was not to produce a musical breakthrough so much as a consumer breakthrough - lifestyle music, jazz with less snap crackle and pop for use in your living-room. That part of it worked, of course.
Oh and in answer to the question I'd say part of the time they slacken, elsewhere they come up with some incredibly memorable phrases.