I read for comprehension and retention, the weight of the material dictates the speed.
Discussion
I agree, but I am interested in the idea of broadening and filling in gaps in my understanding of various things. For example speed reading Russian History. I don't need to retain it all , so long as it forms a sort of skeleton that I can flesh out later at my leisure.
I completely agree that reading quickly and reading well (and objectively) are two different skills.