Its not you.. *L*
Most of the older planes (Stanely, Fulton, Miller Falls etc.) can and often do have a great deal of slop in this adjustment. (the lack of this backlash is what makes so many of the Veritas/Lee Valley and Lie Neilsen planes so attractive to so many) In fact, I've got a new version of the Stanley and it even has a bit of backlash to my surprise. Even my Veritas planes have a small amount. This backlash really makes "tweaking" the iron setting a real challenge, especially when your in the middle of something.
the more you use your planes, the more you'll develop a instinctive feel for how much to turn the adjusting knob. Considering that more often than not, you're looking to pull shavings in the range of <.001 to .007/.008, not much adjustment is required (unless you're using a scrub) I can't say that I've even seen or read of how to take up some of this backlash??? Guessing its just something we gotta learn to live with.
"..... limited only by imagination"
"Just smile and wave boys, smile and wave"
Skipper the Penguin