@ tomas
no I am not clueless, if you look at the time it takes to defrag a large harddrive (and I am not talking about if you are sleeping etc) just about the actual time. You will NEVER get that time back in speed increase.
And how often would you suggest defragging your HDD. Because very very quickly after a defrag you will get to the same stage again.
Lets take a user who uses their PC mostly for gaming. They are not going to be writing a lot of data back to the disk, the only thing that get fragmented wouldd be the pagefile. As previoulsy discussed the windows defragger (that most people would use) cant defrag this. So where would be the advantage of defragging