In the case where the rubber is good I think these can be just as good as the full fix solution. If someone wants to add just one shim then I wouldn't even bother. But of course you can really never add just one shim as you need to replace the other and now your doing two shims. So with a bit more work now you have real rubber. You can also use the rail liner cushion method to cut wafers. There are various attributes to this method that lend more than just what I mentioned. The real issue here is the front of the pocket and the back liner has little to do with anything anyways. If the shelf was extremely deep then it would be more of a consequence. Once the ball leaves the surface its gone and it doesn't matter anyways IMO.(look at where we are talking on a table to see what I mean) When you review the back side of the ext near the rail this point is moot. You can add new rubber but the composition length of the extension near the rail liner behind the cushion is not as relative.
Your point of players adapting is very good. If guys were shooting into dead shims they wouldn't want to play on that table. If you triple shim or double shim with the wrong durometer they are not going to like it.
Sorry if I implied that this was a cureall. It is an option worth looking at. If you showed this to a customer and one side had shims and one had my ext what do you think they would want? If two tables were set up and one had my extensions and the other new rubber cut long, would you bet that players can tell the difference? I wouldn't.
So the answer is, improved method yes, alternative to full yes, is it substitute for a full blown rail mod, lets wait and see( I doubt it and you know why as we discussed before). If we had two sets of GC rails do you really think a player could tell the difference between the two mods. I think it does come down to the player\fighter pilot. The pilot could tell which jet was built better after he flew I am sure. But if he filled up from Getty or Sunoco he wouldn't know the dif.
The pilot doesn't have to know anything but his job.. He can tell if the jet has a problem and doesn't need to know why or be able to fix it. Of course it would help. Like being the Prsident, he doesn't have to know how to make bombs, just where to shoot them.
Titled the thread OTLB extension, I created it. I didn't say it was the way it had to be done and hope that noone ever feels that because I say something that I am saying you or anyone else has to do it this\that way.. Its hard for me to accept the norm. Guess thats why I have a GC V snooker table with 3 inch pockets. Really, if you can add snooker bends and they work, is there a reason why a skilled guy can't do this.
I brought this into the forum as a mechanic gesture, sharing another method that doesn't fit the norm but works. I am sharing some of my methods which is what people are asking me to do.
IS there a better way to do things, yes there is. Is there a better way if you don't think about one. no there is NOT. I could start another thread to address another method but I know everyone would probably disagree with it as it costs more money than the way they do it now. Much the same as your rail ext's arguement. There is a more professional way but getting the job done is also very important. There are more ways to do things then the std method as you know.
I developed these in my R+D room(my bathroom) to address the RKC challenge. Just watch me go into a poolroom and slap down some cloth with tac strips and rail ext's with these little guys, and then I will level the table with my laser. As I said he has inspired me. Some people work because of desperation, some from motivation some from inspiration etc.
Again, I am sharing and as I stated initially, this is only for your consideration.
Thanks John