Why can't I use Extended DOE for G-Optimal and VIF-Optimal in DX?
With the Enhanced Template Option, we basically append a "mini" CCD sampling points within the regular CCD sampling points,
where the axis point "alpha" for the regular CCD is evaluated using its equation (for Face-Centered and Rotatable), and the "alpha"
for the mini CCD is just taken at half of whatever the "alpha" for the regular CCD. It is believed that the appended mini CCD won't
affect the statistical essence of Face-Centered and Rotatable.
However, it is not the case for VIF- and G-Optimal CCDs, because the "alpha" of the regular CCD is optimized with a certain statistical criterion that the second "alpha" of mini CCD also needs to be optimized. At the moment, the optimal "alpha" of the mini CCD is not
yet implemented. Therefore, we block the Enhanced Template for the VIF- and G-Optimal CCDs.