Hard up and down shifts will get it to ratchet up tighter, but most, including myself have the problem of not ratcheting down resulting in a chain that is so tight that it is hard on primary, tranny & clutch bearings and produces a howling sound similar to a turbo.
Burt Baker has built a cottage industry around HD drive train failures and here is what he says about the automatic chain adjuster.
The Attitude Chain Adjuster solves the issues associated with the stock auto chain tensioner on 2006-Later Dyna 8 2007-Later Softail/ Touring models. The first moment the chain has enough slack into it to ratchet the shoe up another notch, and thus tightening the chain, it will. One notch tighter might not be an issue, but you don't have any control of when this mechanism stops tightening the chain. The end result in many cases is the primary chain is so tight that it will start wearing out left side motor case bearings, inner primary bearings, clutch hub bearings and transmission output gear bearings. Our manual chain tensioner allows you to adjust the chain to the proper 5/8-7/8" (cold) freeplay, and never have to worry about the chain getting too tight. We offer this chain adjuster for fitment with stock outer primary covers, as well as a package deal with the Bully Primary Cover.
The other option is Hayden M6 and in this case one that I favor over Burt Baker’s Attitude Chain Adjuster.
IMHO it is not worth your time, primary fluid and possibly gaskets, to mess with HD’s Auto adjuster. If you are having problems have a Hayden or Baker standing by to change out.
I have no engineering background or training what-so-ever but I did grow up on a tropical island and fished more than I went to school developing, at a very young age, a strong sense of how fish hooks work and Harley’s Auto tensioners are similar in all respects to fish hooks.
Then add to that Harley's elimination of the inspection cover requiring you to take off the floor board, outer primary and its associated fluids and gaskets just to measure your chain deflection would be cause for me (if I were king) to fire every engineer responsible.