Generally a hard course is indeed a hilly course. One where you keep having to change gear. Every time you climb, you lose time and never get it fully back on the descents.Out of interest, what makes you local 10 a "hard" course? Is it hilly?
Road surfaces also make a difference.
A hard/float morning is usually a factor of weather and wind or lack of it.
Then you have course design which can have a "gift" start or finish - one where there is a descent in one direction only.
And what I call "Honest" courses, where the start and finish are almost opposite each other so hills and wind are average out over the course.
Down here, the "Q" courses are all hard courses and the "E" courses are all fast.