If it is to be adopted widely, at some point it has to go from being distributed among a few million, to being distributed among a few billion. The continual price rise will correlate with that adoption continuing to happen.
So yeah, I understand all these arguments about volatility, but the reason they don't bother me is because they don't seem to point out anything bad about bitcoin in principle, in the long-term, they only point out the negative aspects of using it as a currency while its undergoing its adoption phase. I don't think there's actually any argument that using bitcoin as a currency right now isn't going to work as well as dollars/euros.
Sentiments along the lines of: "For bitcoin to be adopted, it should be stable first" don't make sense, because adoption (demand) drives the instability. That statement is the equivalent of saying "For bitcoin to grow, it should not be growing."
That's right, and it's a feature, not a bug.
Those that do have wealth to protect should be encouraged to use it for productive investments. Mild inflation is one way to do that, and it is healthy. Massive inflation to fund overseas adventurism on the other hand, is not healthy.
As the author of this piece correctly points out, deflation leads to hording behavior. In a world where everyone used bitcoin, the wealth disparity would only grow faster.
Elasticity simply refers to whether the supply can react to price. In bitcoin's case, it cannot, since the supply is determined by an algorithm.
The USD and the Euro, in comparison to BTC, are magnificently stable.
Sure USD/Eur changed in relative value by 100% over the course of 6 years after the inception of the Euro. That's very stable for a new currency, especially in contrast to bitcoin. The BTC/USD rate has changed by 400% over the past 30 days.