They have a mandate to stop all the obstruction, anytime some one falls someone is held accountable, they don't just let them play they look for penalties, there are a lot more chintzy penalties now...in times gone by, there was only a few players known for diving now it's everybody doing it, and they do it because they have a good chance of drawing a penalty.Keep in mind that it really hasn't been that long since they started using 2 refs. So relatively speaking, I don't think that the job is really that much tougher from what it used to be with just 1 ref responsible for the whole ice.