Greg: Remind me about the images and what was included in them. I think I still have some and one with about a size 12 boot with the underfloor in a computer room.
The reason for the "flexibility" rule calling for the EGC at all times is because CMP 9 went out into the field and found that most of the compressors on roofs were with loose connections, and the flexible metal conduit that was used was not secure in many instances.
I think that the they did this around the 1981 or 1984 NEC cycle. Maybe someone can check the TCR and TCD
