I would love to know how they could possibly be a shock hazard. I have a piles of these (for travel) and they are solidly build and almost only plastic.
The only way they could break, I think, is if they fell apart somehow.
There was an incident in Norway recently where a school kid was unplugging an iPad, and the prongs came loose from the charger. This left exposed metal bits protruding from the live socket, and the kid has apparently reached in to remove them. Kid survived, thankfully.
From the images i found it looked like the assembly was basically pushed into the charger. There seemed to be some notched on the metal bits that would be inside, likely supposed to latch together during assembly, but i guess they could come loose if there was enough insertions and removal.
I may have one of these dodgy plugs from a 2011 11" MBA that I started using as a spare so to preserve my most recent replacement. (third or fourth bent/broken cord)
When you place either hand on the MBA casing beside the trackpad you get what feels like a buzzing in your lower palm. If you are shirtless (common on these balmy summer nights) and touch your stomach against the edge you get a definite kick like you burnt yourself.
From the images i found it looked like the assembly was basically pushed into the charger. There seemed to be some notched on the metal bits that would be inside, likely supposed to latch together during assembly, but i guess they could come loose if there was enough insertions and removal.