There’s an Apple support article that details how to reduce cable strain and damage on your MagSafe power adapter but that’s about it, it’s not even in the getting started booklet that’s in the box with the Mac (at least it hasn’t been on any Mac I’ve owned). Unless you decided to one day research the best methods for keeping your adapter free of cable damage then you’d never really know. Ironically, this was the exact same problem Apple’s smaller profile 30-pin dock connector cables were experiencing since they shrank it and removed the need to pinch the sides - customers would just yank the cable.
With the previous T-shaped connector, pull the cable in any direction and it’ll detach. With the L-shaped connector, pull the cable in most directions and it’ll detach. The one direction it won’t detach is if it’s pulled back away from the rear of the Mac (or the rear-right of the Mac), the cable can’t detach since the MagSafe port is recessed. All it needs is a sharp tug of the cable backwards and it’s enough to cause the exact problem MagSafe tried to avoid - a flying Mac.
By reducing the height and increasing the width of MagSafe, Apple could move back to the more versatile T-shaped connector that all new MacBook Pro/Airs ship with. The magnet is still pretty strong (in fact I think it’s still a little too strong) but the cable’s strain relief appears to be better and my cable has been in constant use for the better part of 8 months and it looks just as good as it did out of the box.