First: whose problem is it that China has "too many dollars"? China's or the IMF's? I say it's China's. Why does the IMF need more dollars?
Next: what price should the IMF sell at? Iacono says the IMF has 2,817 metric tons (MT) of gold. My conversion at 32,151 Troy ounces per MT is 90.6 million ounces. If China has $1.3 trillion dollars of foreign exchange reserves (FER) and if the IMF wants to buy even 20% of China's FER or $260 billion, the IMF needs $2,870 per ounce ($260 billion / 90.6 million). With gold at $728 as I write, the IMF needs a "quadruple" to retire 20% of China's FER. Does Iacono suggest the IMF sell a real asset GOLD, to buy paper dollars? If the IMF wants dollars all it need do is call Helicopter Ben (HB) and have HB print them. HB can print them and make a big profit. What do dollars cost HB to print? Virtually nothing.
By the way, the IMF held gold sales from 1976 to about 1980. Iacono should see what happened to these gold sales involving about 25 million ounces.
Perhaps Iacono thinks the US should "redeem" China's FER. We have 8,133.5 MT of gold according to Iacono or 261.5 million ounces. If we were to redeem 20% of China's FER we need a price of $995 per ounce. For the US to redeem all of China's FER would require $4,971 per ounce. The bullish case for GOLD is easily made.