Good question!
This is just my take on it. Like the Mariner's Compass block, there is a lot of different size pieces and points that would be hard to match with regular piecing. And like you mentioned, some pieces are very small as in some circular patterns.
I'm not very good at PP, but I want to make a Mariner's quilt, so am trying to learn as much as I can before I start a whole project. The January BOM is a paper piecing block that is not too difficult. You might want to go to that posing and see if you would like to try it. There is a youtube video that is really good at explaining it also. I'll find it and PM you with that link.
Some people would rather PP than regular piecing. I haven't made up my mind yet.
Here is the link. It is very basic and easy to follow:
http://www.youtube.com/watch?v=8uaW2...re=uploademail