I just dug out my IIc from the depths of my gear cabinet and donned my glasses -- with progressive lenses, which often make photography a chore -- and I find that I can see the entire frame without having to move me or the camera around. If I want to see the edges of the viewfinder, however, then I do need to move around some. But since the frame represents the image, I don't see much need for that.
Anyway, bottom line, I don't find it uncomfortable to wear glasses when using my IIc. Heck, I've worn my glasses when shooting with my old Canon rangefinders and their super tiny squinty VF openings, so this IIc is quite comfortable in comparison.