As for the Clear Spheres, not too useful unless you’re planning on maxing out your characters’ stats. If you are, it’s the only way to max out HP or MP, if you’re maxing out everything else, so definitely useful in that case.
laterz
lone wolf
I mean that I have cleared all nodes of lesser additions in Tidus, Kimarhi, Yuna, and Auron’s parts of the Sphere Grid, and then replaced them with the max attribute node according to placement.
For example, I come up to a Defense +1, I clear it, and use a Defense Sphere to make it Defense +4. If I come up to a blank node, I use the HP Sphere and make it HP +300.
Well, that’s probably not 2/3, but close enough.