Yea of course protecting  your private key is a necessity. The thing is, it is also good to have it with you, making it mobile, you can save it in your smartphone just in case of emergency and for safety I went as far as coding my Private Key.

E.g (Adding more digits & letter and also removed some);

77e7577Y5373241d6ccddedb6a95fH5Fa9c2391443fe352a81a028944fdc48eeecd