I fully understand how this can "sound" harsh. I really do. My understanding is that the underlying theme is the supreme sovereignty of God. He is the potter and it is not for us to question, etc.
As I learn more about this it seems to me personally that the issue of perspective is very important. From God's point of view everything is already a done deal, He already knows which names are and which are not in the Book of Life. However, from our perspective we have no such knowledge. That is why we are to spread the Word and minister to the whole world as if all were the elect. So, even with this (new for me) view, I will carry on as a Christian pretty much the same way.