Godric says:
Agreed, Edge/Effort is the most confusing aspect of Cypher. I don't quite get it either.
I look at the pools as how much stamina you have at the type of task.
A Might Pool of 10 abstractly you can spend X hours lugging sacks of grain per 2 points out of the pool. (Work doing manual labor)
Might Edge would be how skilled you are at doing something physical so you can move more bags faster. (Burlier worker doing manual labor)
Effort would be an exertion when you want more of an effect but don't have the time. (You're done for the day after these last 4 sacks are moved so you go in one go.
Does that help or confuse you more.