One thing that helps me when I am chasing a grind is to mark the high spots. I use those crayon pencils that you peel. Sharpie will work, but then you can't use it on handle materials also. I look at the grind from the end, and decide where the high points are. Mark those high points and go back to the grinder only removing the mark then look again. Do not continue to run the belt over the low spot!!! Keep marking the high places and removing them until you get them close, then blend into the low spots (thin edged parts of your grind).
This may seem so stupid simple, but I think it is critical, and I have observed it in multiple stock removal professions. There are a lot of professions that rely on stock removal techniques. They invariably, set or decide on a low spot in the design, then work the high spots down to match the low. Barbers, landscapers, and flint knappers are a few quick examples. So, any time you are chasing a shape, stick to the high spots and stop touching the low spots until you're ready to blend and finish. This is important for handle shaping just as much as it is for grinds. I use those peelable crayon pencils for this on handles and blades. Mark the high spots, and only touch those. Any ajustment of the low requires a total re-shaping of the high spots to match it so stay away from them.