Never left a cable in a frame…

Don’t tend to add systems that weren’t original – There are exceptions to that rule –
Short-term stabilization awaiting budget realization – Bringing things up to code for adaptive reuse, Working within an existing budget to save a building which would otherwise be lost, etc.

More than a few inches of lean, does offer the opportunity to insert tenons, new or the commonly found empty ones.

Everyday come-a-longs don’t have the uumph you need to pull tons of building back to plumb, Grade 8 chain and ratcheting load binders work well ( use your come-a- long to get the chains taut before slipping on the binder ) I have Steamboat Jack that I get out for seriously listing barns. ( Found it at the best TF tool auction I’ve ever been to with the moderator of this forum and a bunch of other framers, and somehow I didn’t go home with seventy screw jacks, but that’s a story that’ll have to wait for more time and maybe a campfire )

Your right on with your nightmare scenario and adjustability. See it all the time with added arches on Covered Bridges, some well intended but uninitiated road agent comes along and tightens the rods to the point where the tension webs in the trusses are no longer performing, all the load is transferred to the arches, and the dominos begin to wobble…

Best to avoid it completely IMO.

Besides, somebody is bound to decide they need those come-a-longs more than the barn does. Why not just nestle in a set of passing braces once the frame is conditioned

And again, restoration is as much a rigging trade as it is one of carpentry –

Here’s a super useful file for your perusal.

http://www.petrospec-technologies.com/Herkommer/knots/FM5-125.pdf