Yes, Mater Public Key = Chain Code

Revealing any private key for any type of Bitcoin wallet software kind of lets the person you revealed it to steal all your money. I think that possibly the Bitcoin Magazine article has a mistake in it, or is maybe written in a way that gave you the wrong impression.

If you want to keep a backup for a gift to your friend, just keeping the private key won't be enough. You need the Chain Code too, as that determines all the addresses that the private key unlocks. The private key on it's own is like having a real-life key, but you don't know which lock it opens. When you know the house (think: address), and you have the key, then you can get through the door.