Originally Posted by mortenb

It can be used to show a particular ad based on previous click patterns, which can really improve conversions!

And 10 zillion other things. I know that you are a very very competent developer (I have even told my clients to go talk to you when I haven't had time to work with them), but you clearly have a limited understanding of what the Markov concept is capable of. I'm not trying to piss you off, it is a pretty advanced concept and as webmasters we usually only see a very small part of it.