as we know, canon changed their mount in the 80's, meaning that older lenses were no longer compatible. but try mounting a g mount lens on an f4. okay, so you may not want to shoot with an f4, but maybe you want to use some your g lens with some of the new mirrorless cameras....no can't do that. if nikon were going to make the backwards compatibility of their lenses obsolete, then they should have just changed the mount like canon did.....then they would have a more versatile mount. the only reason they don't include the ring, is to cut costs. hey i've bought a couple of g lenses, the 24-70, and the 70-200, and they work fine on new cameras, but i prefer the more tactile feel of a ring, I find it quicker to use, and i wouldn't have thought that it would cost nikon alot to implement. give me a physical dial on camera over a command wheel any day.