Any USD to bitcoin exchange price reflects both a bitcoin buyer and a bitcoin spender (seller). The bitcoin exchange price can only increase through people spending bitcoins on USD. Besides, if this argument that "the only rational thing to do if you own a deflationary currency is to hoard it" is correct, then that implies that "the only rational thing to do with an inflationary currency is to buy a deflationary currency regardless of the exchange price."
Ummm, no. The bitcoin price can only go up if people are spending US dollars, Euros, etc on Bitcoins, not the other way around as you describe it. You do understand how currency exchanges function, do you not? If people are goign to an exchange, giving the exchange bitcoins, and then taking dollars for said bitcoins, the ratio of bitcoins to dollars within the exchanges holdings has just gone up, lowering the number of dollars it takes to buy a bitcoin....... so if the bitcoin takes MORE dollars, euros, etc to buy, then the opposite must be occurring.
