This is the time honored method by which I lap valves. This is called a "basic" valve job and is primarily used for refreshing the valve faces and seats. Also, it was stressed to me by the old gentleman who taught me how when I was a kid, the importance of being able to see the actual area where the valve seats. I think it's so important, I even disassemble new heads and lap the valves. Yes, while it's true, the modern Serdi machine is the way to go, nevertheless, I will come behind that and do it old school. As my usual disclaimer, this is "my" method. Don't like it? Don't do it.