There is some rhyme and reason to the order, so there is a benefit to going in order if for no other reason than you may miss something important taught in an earlier lesson that is not repeated. Just remember that the course is written for a mythical "generic" student. Few of us are a true blank slate. We will each have our own past experiences and reasons for taking the classes. Some areas will be entirely new, and some simply review. There is also the matter of maintaining your interest. I jumped around quite a bit to fit my interests and deficiencies just because that is how I work. I will occasionally go back and revisit a section that I have already gone through to try and improve or to see if I can pick up something new the second or third time around. I also like perspective and can recommend Marshal's Perspective course when you feel like you need more than what is provided in the Drawing Fundamentals course. Quite a few lessons from that class are available free as well.

If you jump ahead to perspective too quickly, there's a high degree of likelihood that Marshall Vandruff will appear under your bed at the stroke of midnight to steal your T-square and triangles, so be careful! The only way to rid yourself of the curse is to say "Receding Divergence" three times in the mirror. That very real warning aside, there's no harm in reading a few chapters ahead to start to familiarize yourself with the concepts, just don't let it derail your forward progress in earlier lessons!