The clock doesn't lie.

The bad thing about track speed work is the hassle of going to the track, along with the stress and strain it puts on various systems of the mind and body. There is, however, an up-side to this type of training. It tells you exactly what kind of speed shape you are in (if you give an honest effort). It allows you to adjust your training to the reality that you're not ready for a fast race time just yet (if that's the case), or it gives you confidence.
My third trip to the track on a warm,humid and breezy day, had me doing ten 400 meter intervals with a 1 minute rest.
The results: 77,77,75,76,76,76,76,76,77,71. I finished the work feeling tired but not wiped out.
I know that if I maintain an 80 second pace for 3.1 miles I will run a 16:40 . My goal for now is to break 17:00.
Today's training results give me reason to toe the line on Saturday with confidence.
Starting at 80-82 per 400 should feel comfortable, then get engaged in the race (hopefully there will be the right competition), then get tough when the pain comes in the later stages of the race (I call this the 'window of pain').
Getting under 17:00 should happen if conditions are right and I run according to plan.