The linked polarity diagram is definitely incorrect. These magnets are non-standard and have a dual set of poles for EACH magnet (The outer ring is North up, and South down, and the inner ring of the magnet is South up and North down).
Check out page 86 of the Accessory style guide. https://developer.apple.com/accessories/...
For those asking, Apple published a revision to their Developer Style Guide for physical accessories that includes all of the information you could need about the MagSafe standard.
Once they have, you'll be able to view a graph of their reputation gained over time.
Here's a preview of what the graph will look like:
No reputation gained yet.