Running taller springs will have the same effect on the CV as a tall spacer. The CV only cares about the relative height of the differential compared to the center of the wheel. That's why people with large lifts do diff drops.

CV vibration may well occur at smaller angles than 30 deg, but my post was originally about breakage, not vibration. Not many people crank their steering wheels to full lock while going fast enough for vibration to be a factor, at least and live to tell about it.

Just went out and did some measurements on my stock '06 Sport, to put some science into this. The CV joints are 12 inches apart, and the CV offset is a negative 1.5 inches. That gives a CV angle of 7 degrees. Fender height is 34 inches. If I lifted to 40 inches without moving the diff, the CV offset would go to a positive 4.5 inches. That would be a CV angle of 20 degrees, still a lot less than the maximum steering angle. Dropping the diff 1.5 inches would make the CV angle a mild 14 degrees. That's assuming the entire lift was a suspension lift. If part of it was a body lift, which doesn't raise the diff, the angles would be even better.