I discovered yesterday that the reason for sluggishness in section editing was the result of the 2D hardware accelleration being on full. Once I set it to off, everything was zippy.
It apparently changed when I loaded a previous Work Environment looking for some cosmetic changes I had made previously.
Intel i7-6700@3.4GHz 16g
GeForce GTX 745 4g HP Pavilion 25xw
Windows 10 Archicad 26 USA Full