I think that when we assume that inflation hurts the poor, we assume that things like mimimum wages, marginal tax rates, welfare and pension allowances, family and housing allocations cannot be indexed, when the fact of the matter is they can be (and indeed, in France though not in America, largely they are).

I simply take Milton Friedman's word and suppose that monetary theory's implication is that inflation is simply a tax on holders of the currency being inflated (again, largely by monetary policy). Holders of currencies tend to be in direct proportion to wealth denominated in said currencies. Thus inflation can be quite progressive, assuming of course that pensions, after-tax wages and other allowances are properly indexed.

Of course, the economist in me recognizes that there is economic inefficiency in inflation, ie, there can be too much inflation, as seen in a good numer of studies correlating high inflation to lower economic growth. Which makes sense given the amount of energy folks waste trying to avoid its effects in environments where inflation is quite high.

But 2% is not that benchmark. 4% probably is too low as well.  

I would be ashamed to admit that I had risen from the ranks. When I rise it will be with the ranks, and not from them Eugene Debs