The MagSafe 2 connector fails that balance test. Badly. The magnet is too weak. It’s so weak, it keeps falling out. It falls out if you brush it. It falls out if you tip the laptop slightly. It falls out if you look at it funny. It’s a huge, huge pain.
That weakness is compounded by a second problem: a return to the “T” design of older MagSafe connectors. In other words, this thing comes straight into the side of the laptop — the cable shoots out at 90 degrees — instead of hugging the side with the cord parallel, like the old “L” connectors. As a result, it protrudes a half inch beyond the left edge. You can’t rest the left side of the laptop on your thigh. It’s constantly getting bumped. And since the magnet has all the grip strength of an elderly gnat, guess what happens?
Can’t say I’ve noticed this with the 15-inch MacBook Pro with Retina Display, but I don’t move that around while charging. Maybe it’s more of a problem with Airs?
I can agree with Pogue on this one, the adapter is very annoying to use, especially when the laptop is on your lap. My leg knocks the adapter out about every 30 seconds. Maybe this indeed isn’t such an issue on the MBP-Retina, but I don’t have one to test the MagSafe 2 adapter on.
The MagSafe 2 adapter does work, I use it every day to plug in my Thunderbolt Cinema Display to the MacBook Air. It is only when you try to move the laptop around and use it on surfaces other than a desk that the issue becomes apparent. I wish Apple had thought this adapter idea out just a little more.