Curious if Pete managed to talk him down to a simple tell-tale gauge, or did the steel posts actually go in?

Cruel cliffhanger cutting Pete off mid-sentence like that. Did you end up talking the engineer into tell-tales, or are there actually six steel posts down there right now?

Loved this—especially the point about a laser level mistaking a century-old resting posture for an active emergency. Equilibrium in old masonry almost never shows up plumb.

Half the tuffeau cellars along the Loire have a four-inch belly that has been locked dead in compression for two centuries. The second you introduce rigid steel to fight that kind of settled weight, you usually just shear the mortar bed.

Really appreciated this. A flat laser level tells you deviation from a datum, but it completely misses that the stone found its own stable thrust line a century ago.

Locking a mass wall rigid with steel usually just shears the bed joints right above the new pins. Stick a few glass tell-tales across the lime mortar instead—guaranteed they won't register a millimeter of movement in a year.

My first deviation map of an old brick sluice near Arnhem lit up bright red with lateral shear. The water board surveyor didn't even look at the Grasshopper script—just told me the lime mortar settled into that exact sag before the French left.

Don’t leave us hanging on Pete’s verdict, though I’d bet good money that wall stopped moving before the engineer was even born.

This is brilliant. People forget that historic masonry doesn't always want to be plumb—it finds its own equilibrium, and usually did that decades before anyone showed up with a digital level.