And why is that an issue? The most that can happen is that there is no saving of the Baht or the Rand outside the taxation area of those currencies. Assuming t

And why is that an issue? The most that can happen is that there is no saving of the Baht or the Rand outside the taxation area of those currencies. Assuming they are fully floating. In which case the central bank will be doing nothing other than offsetting the domestic savings in the currency of issue. Because sector balances have to balance. The concept of "reserve" is utterly flawed. People hold balances of all sorts of currencies for very many reasons - largely working capital, but also for insurance and for prestige.