Thanks. Follow-up question: couldn't that be treated as optional? Like, couldn't a person just take the barrel to torque if they wanted to commit to a certain level of repeatability with a given barrel?
Yes.
On the Terminus, I personally have two of the QC Zeus actions, one for PRS and one for hunting. I have not seen any zero shifts with these two rifles. I just have been wringing the barrel to the action, and hit the set screws with the fix it stick and it has performed well. I too was skeptical on these, and if it didn’t work, I still have a great action with a normally torqued barrel. I do think if you had a barrel that had a shoulder and tenon that was not machined as good as it should have been, you may see some problems with zero shifts.