It is needed in some cases, other times it isn't. Just depends on the setup. Just because a company makes and sells something doesn't mean everyone needs it.
Look at the first picture he posted and tell me how would you ever hook up the throttle cable if he installed the adapter that moves the linkage stud out another inch? The throttle cable mount has it positioned in so far already it nearly rubs the carb body. If it had a different throttle cable mount that positioned the cable a couple inches out farther the adapter would probably work.
