When you have an infant you have to do whatever you have to do to make it work. That kid is not on a respectable schedule, so eating and lying down are extreme luxuries. That is unless you use this method. If you have to hold your child anyway, you might as well make them useful. As long as you don't drop them then everything will be fine. Even if you do drop them there's no way of knowing if they were destined to be slow or if you caused it.
Some people say that having kids is the greatest joy in life. Others don't say anything and look tired all the time. You know what the difference between those two people is? One of them is rich and the other one is poor. If you're rich having kids is great.