I got it now... by tightening the pockets, the point of the pocket is closer to the apex at the center of the pocket, there by moving closer to the shelf itself... makes sense when I actually thought about it an referenced your grid picture.
Yup. RKC mentioned that and it didn't make sense right away until I thought about it for awhile. Having a photo and the grid at that time would have made it a lot easier for me to see it.
I'm really curious to see how your table comes out. I have a complete wood shop, and after talking to Mark Gregory about the work and my skill set, he thinks I could manage the job as long as I have all the specs. The hardest part was figuring it all out in the first place. Mark and Glen really changed the game with all their research and experimentation on rails and pockets.
Will you be taking photos of the project and posting a thread about it all? I won't be ready to think about any of it until my table needs new cloth, and that is at least a few years away. Still, I'd like to get as much info as possible before time, just in case I decide to go through with it.