Interesting thread and posts. Just a couple of observations from my high school coaching- hoping for some feedback as well.
Our winter off season is four months with no indoor track races. The winter can be harsh- lots of snow/ice and we have limited outdoor areas to run. However, our kids dutifully go out and plug away, even in 0 degree weather. My point- they train consistently. We focus on 1 long run a week (25% of weekly volume) and only run 5 days a week. When we can, we will run 1 tempo run a week. This is usually 3 - 6 miles at a quick even pace. Again, because of the weather- we don't get one of these in every week. We rarely even get in strides because the track/sidewalks are covered in snow/ice and I refuse to train indoors.
Now, before track starts we run a 1600M time trial. Our kids run to within a few seconds of their PR or they PR. No one tanks it and everyone feels good about the performance. Doesn't matter on the performance level- from 6:00 runners to 4:30 runners.
I always get excited, we do a traditional 1600/3200 training plan, using Jack Daniels training paces, and the kids improve. For example, I kid that runs 4:39 runs 4:29. A girl that runs 5:25 runs 5:15. On average, about a 10 second improvement from March 1 to May 30th. However..... I always feel let down by the improvement. Is 10 second improvement in 3 months good? As I write this, I think it isn't bad. But, I always feel like a 15 second improvement is possible but we blow it.
I haven't had the guts to try this, but I wonder what would happen if we didn't do any speedwork? If all we did was just work on becoming aerobic monsters, do tempos and a steady state runs, throw in some hills and strides and the end of a workout..... would we improve the same or would we run faster?
This may be beyond the scope of the thread, but am just curious to hear people's thoughts.