Sounds a lot like it's a road race for everyone but the Cat 5s, and the Cat 5s are doing a half hour crit. Not a terrible thing, really. Or, maybe it really does suck and that's all there is to it. I wouldn't pay for a 15 mile road race.
Perhaps it's a typo?
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter