The math and calculating takes pretty much no time at all, I don't thinks that's the main issue.
The problem I run into is having to type up the whole post. This takes the majority of the time it does to ref.
Here is a couple suggestions I would make:
1. Aside from reffing, you could make a different person called a writer. The refs could pm the calculation and they could write up the actions and pm them to the ref so he/she could post.
EDIT: I liked this idea after some thought, so I wanted to expand on it. I came up with two different ways of doing this. First the buddy system. The calculator takes a test towards calculating, and a writer writes a post from random calculations as their test.
Once you have passed your test you will move on to another thread. In this thread you will post your activity level and possibly time zone. Then you can find a writer/calculator who seems to be as active as you. This becomes your "buddy". The calculator will send the writer the calculations from the battle. The writer will then send the calculator the written post. Then the calculator/writer posts both the calculations and writing in the ref post. The buddy that did not post can have some written credit in the post.
The other method is just a writer thread. The calculator posts their calculations into the writers thread. A writer will claim the calculations. Once they claimed it they must write the post out for it and send it to the calculator. The calculator then can post it, giving the writer credit in his post.
2. You could allow the refs to not have to add writing to their post until we get enough refs to deal with all the battles.
That's really all I have.