First, I'm a big believer in speed work.
Most people think that they are doing speed work when in reality they are doing pace work.
I thought that this was a trivial choice of words at first, but three years under this system taught me the value. This is especially important to the 10k runners who won't step on the track till the first meet of the year. Admittedly, my direct experience does not extend much beyond the 1500, but I maintain the importance of quality intervals for any track runner. I do believe mileage is important, but highly overrated. This is a case where quality is far more important than quantity.