Bitcoin does NOT do what it was designed for. It was designed to be an alternate form of currency but it fails to serve as a currency while exacting a high price merely to exist. As an economist I'm sure you know that currencies are mediums of exchange relying on the trust of the exchangers that the exchange rate for the currency is relatively stable. The Bitcoin protocol is so kludgy, expensive and slow that the only transactions it's a part of is the sale of Bitcoins, done primarily for purposes of speculation. Given its essentially deflationary nature (limited number) it can only really serve as a speculative commodity, not a currency, which directly negates "Satoshi's" original intent.