MS PFX - How not to design a crypto standard

PFX from Microsoft is an outdated standard for storing an asymmetric private key and public certificate as an encrypted file. It is relevant today because 1) it is the precursor to the widely used PKCS#12 standard from RSALabs and 2) it is so horribly confusing it serves as a counter-example of how not to write a standard (at least, according to this article.)