Ok, so the gap in the back you got rid of by grinding down the grip and blade to where the tang is full/flat.

This may actually stengthen the blade (depending on the original radius?) however...

I hate it. Does not look good, and i love the flat back spine for thumb placement.. (don't get me wrong, not waiving the 'moron' flag or anything... I get it.. its just not for me... how bad was your gap to prompt this grind?)