Thanks Matthew and Dwight ... I’ve been playing around with this (way too much)
To answer Dwight's question directly, no I don't need this much detail for 3D. As a newbie I fall into the trap of not thinking about things like this when I detail. I had an AutoCAD block so it was a simple copy/paste, magic wand spacebar click to make this fills in the profile manager and I was good to go or so I thought.
I tried a 'dumbed down' object (without rounded corners) in a blank file (so there would not be the intersection issues Matthew described) using a closed polyline of straight lines then using Dwight’s magic wand method described below. Even with a dumbed down object, the section processing time was instantaneous when using the beam tool and 60 seconds or so when using the wall tool.
So when I introduce a curve to the polyline (and tweak the magic wand settings to an acceptable curve resolution level) using the beam tool still produces near instantaneous results. Problem solved.
Maybe that's just the way it is, but I am still curious why the same profile (in this case) takes substantially more time to process when using the wall tool in lieu of the beam tool.
Thanks for your help.
ArchiCAD v27 (since v11)
MacBook Pro M1 Max, 64GB
macOS Sonoma