But if a huge chunk of major global currencies go belly-up at the same time the world has much larger issues than Libra taking a, say 20% dive - the volatility

But if a huge chunk of major global currencies go belly-up at the same time the world has much larger issues than Libra taking a, say 20% dive - the volatility in all kinds of sectors would dwarf that. All other aspects of the design strike me as either dumb, redundant or dangerous, but this would be the one part of the system not to worry about.