So I was wondering, and I would like to hear other's input on this. If the sole purpose of providing a sapphire crystal on a watch is to prevent, and in many cases, eliminate the crystal from being scratched, why is anti-reflective coating applied to its outer surface? I can't seem to understand this. Granted it may provide a higher degree of readability in certain circumstances, but over the long run (years or even decades), it may cause perceivable scratches and imperfections on the crystal that are NOT covered under warranty. An example of this is the Planet Ocean. I own a SMP 2254 and this piece only has AR coating on the underside of the crystal and the dial can be seen perfectly in many and almost all circumstances. So, it seems like coating both sides of a sapphire crystal has no benefits, but rather only shortcomings. Any thoughts?