> With fiat you still have those technical limitations (someone could create indistinguishable counterfeit money and dump it on the market).

I think there is more than technological limitations to making this happen. Not only is counterfeiting considered a major crime by the state (who has a monopoly on violence), but the amount of "money" in circulation that has a physical representation is dwarfed by "money" that does not. Even if you doubled the physical currency in circulation you'd only increase the "monetary supply" by 10% or so. Plus there are huge logistics issues with moving that much weight/volume without getting caught.

> Someone can get power at the Fed and decide to double the money supply over night.

I think that if the function of government breaks down to this extent, I will have bigger problems than currency devaluation.