In my experience, there aren't fewer x-ray lanes, but there are more cases of 2 x-ray machines feeding into a single WTMD.

This slows down the line quite a bit with laptop carrying passengers like myself, because I refuse to release my laptop onto the x-ray belt until the WTMD screener waves me through. I often end up waiting--and totally stalling the x-ray line--while Pa Kettle from the other side divests himself of his giant alarming belt, or Ma Kettle divests herself of jingling jewelry.