You can use the X/Y Weighting options in the DGI Gridding Options dialog box to give unequal weights for the X and Y directions when you re-evaluate a grid point. Here is an example of how different weighting options will produce different gridding computation results on your map:
No rotation: X=1, Y=1. View image
45 degree rotation: X=1, Y=1. View image
45 degree rotation X=0.1, Y=1. View image
What do you want to do?