Complex sentence: The separation of platelet dynamics into three stages is useful in this regard, but it is artificial: in fact, each stage is initiated in rapid succession, and each continues until the trigger for that stage is no longer present, so there is overlap.
Split into simpler sentences: The separation of platelet dynamics into three stages is useful in this regard, but it is artificial. In fact, each stage is initiated in rapid succession, and each continues until the trigger for that stage is no longer present, so there is overlap.