wilbur
Can I take another stab at describing what you're seeing?

It sounds like the goal is to take a beat up chisel, use your Delta wet wheel grinder to grind it at, say, 25º, transfer the chisel to the Veritas MkII for honing, also set for 25º, and then see the metal wearing away nicely on the edge and the heel of the bevel as it would if you were freehanding the honing.

What you are seeing instead is that after grinding, the Veritas MkII's version of 25º is a little off the Delta's version of 25º, since the metal is being removed from the top part of the bevel only.

If that is the case, my vote is to go back to your grinder and set it for a slightly shallower angle than wherever you had it. That way when you go from the grinder to the honing guide, you'll only be working the cutting edge, and over time the entire bevel will match the angle that the honing guide is setting, until you feel the need to grind the chisel again.

The other alternative is to use the coarsest, most aggressive method you have of sharpening with the honing guide. Something like 80 grit sandpaper. But although I've done that at times, I think it's still easier to use a grinder.

Eventually you'll have to grind away the metal at the top of the bevel, regardless of what you do. The problem with the overshoot/undershoot method is that you'll be removing that top part of the bevel with your honing, and as I mentioned before, it's a lot easier to do that with your grinder than with your honing guide.