I've never purposefully ladder-walked (although I've been known to hang from a joist and pick up and move the ladder with my feet...) but waaaay back in my young and dumb years...
I was apprenticing in Richmond VA, summer of 86. We were hammering out dwellings left and right, fast pace environment... I was told to rough-in for a garage light and garage door opener recept, which on the unfinished floor was a good 18 feet up.
The rickety 12 foot step ladder just got me in reach on the "No Step" step, the top plastic one. While nailing the box up for the light, the ladder started walking on the uneven gravel surface, and toppled over with me hanging from the joist... the other guys had to stand the ladder back up, a fall onto all the debris would have been bad...
I've never had a bad ladder experience since... I'm extra careful with my ladder placement and usage now... (I do on occasion step onto the "NO Step", but you know how it is...)
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