The other problem with the column approach is that it totally complicates the handrail, which has to be continuous. Although I think the IRC only requires a railing on one side, so you could move that to the outside in some cases.
Since the 6" depth is only related to where you are stepping on, could you put in a short wall (lower than the handrail heigh - 24'?) to get the min required 6" step? This way you can also put a standard continuous handrail on the inside wall.
The other problem with the column approach is that it totally complicates the handrail, which has to be continuous. Although I think the IRC only requires a railing on one side, so you could move that to the outside in some cases.
Excellent points and thanks for sharing.
Since the 6" depth is only related to where you are stepping on, could you put in a short wall (lower than the handrail heigh - 24'?) to get the min required 6" step?
This way you can also put a standard continuous handrail on the inside wall.
It should be okay if the area measured is on the inside like you're suggesting.