The attached image is from my mileage / time build up through last Spring.  As you can see I alternate 1 week on with 1 week off.  This approach is atypical, and not what I would recommend for every rider, however, it works perfectly for me.  As I stated in the last post about overload, I respond well to short intense blocks of work followed by lots of recovery.  I used to try to make my blocks of work be the traditional ~3  week build followed by 1 week off, but I discovered, time and time again, that I was always overly fatigued, and sick.  When I finally made the switch to 1 week on / 1 week off I discovered that I was always fresh enough to do the much needed high intensity work, and I was very rarely getting sick.  There is a right level for every rider.  There are numerous factors that come into play in determining that level.  Switch things up in your program until you find just the right amount of overload mixed with just the right amount of recovery to promote maximal gains in your training.

-Jason