TC, I may very well be wrong here, but I understand the quote a little differently.
First, it talks about pushing the CRT tubes to the limits. As I recall, they used to have a sweet spot - a certain resolution with a refresh rate of 75 or even 85 Hz. Tighter resolutions could be used with the cost of the refresh rate. However, you could bypass the recommended settings without getting the "out of range" black screen familiar with LCD screens.
Second, since disabling V-sync doesn't drive an LCD monitor out of range, I believe it's not stressing the screen too much. The high frame rate without V-sync counts partial frames, not fully drawn images.
Again, I may be terribly wrong here. This is just my understanding and logical thinking.