Hill climb Time Trial pacing strategy for short steep hills?
Functional threshold power is defined as the maximum power you can produce for one hour. See for example, this blog.

Since you know that your events are much shorter, you don't have to be so conservative. And since you know your output for the approximate times those courses take,  you should plan that level of output for the race. 

Even with that approach different people will have different ideas on whether to go at the same power all the way or keep some in reserve for the steep bits.

My thinking is that the slow sections are where you lose time, so keep some power in reserve for the steep parts.