How do you explain the same split occuring on the Magsafe connectors? Those are designed to pop right out if you yank them by the cord, so very little strain is going to be put on the wire sleeve. I've seen a lot of Magsafes split in the exact way depicted in the picture.
In my extremely unscientific personal test, the iPod data cable actually came out of my iPhone with less force required than attempting to unplug the MagSafe cable from my laptop.
Of course, that wouldn't be the case when the pulling isn't completely in-line with the socket (although you can exert quite an amount of strain on a MagSafe cable by pulling it out sideways). I think it's too simple to assume that MagSafe wouldn't suffer from this problem.
The explanation given by the parent post rings true for me, certainly I've had these kinds of splits in plenty of cables with traditional "strain-relief" on. I think I'm going to stop unplugging things by tugging the cable. :)
That actually matches what I've observed. Namely that after 2 years of heavy use my magsafe has not had any issues with the connection.
I always remove the connector by tilting it first, instead of pulling. In fact I think there was something in the manual about this - though I can't find it at the moment.
It's a magnet. Shearing / levering is easier than pulling. You're doing it, even if you're not thinking about it, just because you're not pulling perfectly straight. Intentionally tilting it away makes removing it a lot easier than doing so accidentally, though.
i've notice that if you go at an angle it's easier to yank the magsafe cable. straight on it a lot stronger. I'm assuming ti's due to the angle making the force be applied to a small region and not the whole magnet.
The new (90-degree) Magsafe connectors are a step back, in my mind, because if you pull in-line with the cable direction, they will not pop out. There is no leverage to torque it out of the socket and the force is taken up by the edge of the socket. I bet that if you pull in just the right direction, you can pull the cable off the connector before the connector comes out (if the laptop is kept stationary).
That's probably from people using their laptop too far from the power outlet so the connector is under strain, rather than moving closer to the outlet or using the grounded extension. Or possibly from letting the adapter brick hang from the laptop, rather than setting the brick on the table or another surface.
I've had several two MagSafe adapters break at the adapter side rather than the notebook side of the cable in the last 4 years. Apple uses the same sort of strain-relief on that end of the cable too.
