Not to get this discussion off Doonbeg and onto the subject of criss-crossing holes, but I can think of many reasons why I personally consider them a bad design feature, unless there is no alternative--safety, confusion as groups cross, general sloppiness in the play of the course, confusion as to the next tee, confusion as to the line of play, etc. This is just my opinion, but I always consider it to be a sign that the designer had no alternative than to take this course.