Well the owner seems to feel his set could use it, so I'll respect that. But whether it can even happen that way is still in question.
The main improvement the shimming op delivers is in the depth of the image, caused by keeping the largest amount of physical space on the CRT face available, used and in play. Back when the Zenith and Marantz/Philips 65" set guns were 9" while everybody else's 65's were 7", there was a noticeable difference in depth once those 9" gun sets were completely dialed in, over the dialed in 7" gun 65's.
My thoughts are that this applies to any brand of CRT, because it's generic. If you have not seen a Sony shimmed this may not have been evident yet, but I have seen it in all brands and sets I have done the shimming op on. It's subtle, but it's there.
I have found that overscan can be reduced in service menu on Sonys by reducing the H and W with much less hosing of the image than on other brands, tho, I agree with you there. Only brand I can say that about. And Sony is also the only brand where I usually find via the Cantilever Technique that the optical focusing needs no correction and so I am allowed to leave it alone, unchanged from its original factory adjustment settings. One of the key advantages of using the Cantilever Technique for all optical focusing needs, you don't have to disturb your mechanical lens barrel settings if you find it's already dialed in 100% correctly from the factory. A very rare result on all brands but Sonys, but always possible...
The owner is always at choice about how he wants to do the o'scan redux. If he does not want the added depth that the shimming op can deliver and wants to save the extra money, and wants it to just be done within the service menu rather than actually optically reducing it, I am always OK with that and proceed accordingly.
And some sets cannot host the shimming op at this age anyway. Too much aging footprint, or too far off to one side or the other on the gun itself... This all has to be determined before a shimming op can even really be realistically considered. When I show up I am ready for bear, but sometimes after a fully evaluation we find we cannot actually do the shimming op after all and have to fall back on the service menu resizing and correction only version.
But the resizing to get rid of the overscan, one way or another, is always a huge improvement once completed, on CRT tech. Definitely worth doing.
Edited by Mr Bob - 8/21/13 at 9:56am