I was on a long-haul flight a couple of days ago and by coincidence( now you can choose your own in-flight entertainment) I watched a documentary and interview about Reich. He has a good,serious music pedigree - trained with Berio for example - and feels himself to have undergone several changes in musical style,beginning with his move away from serialism, which was de rigeur when he was training. He came across as sincere and explorative in his ideas about music.So he would probably disagree with whoever said that his approach hasnt changed.
   I got the impression that he is particularly interested in rhythm, and subtle shifts in rhythm over periods of time. There's a piece of his that is often played to exemplify this style - the clapping tune (it may have another title). The idea behind it is mildly interesting but the piece itself,involving constant shifts of rhythm as several pairs of clapping hands come in and out of snyc with one another, is not something you're going to want to hear again probably.