This decision is not going to blow up the gold market right now. In my opinion, the repatriation of 300 tons from NY between now and 2020 looks like a compromise which allows for a gradual withdrawal that should not be too difficult for the US to facilitate.

The withdrawal from France is basically a non-event, since the System of European Central Banks has a common policy towards its Gold Reserves, so whether the gold is in Paris or in Frankfurt doesn't really matter as long as it is within the Euro zone. They probably do this to silence the public opinion claiming the repatriation of German gold and France has enough gold to accomodate this request without any pain.

What is remarkable is that they leave the 450 tons of German gold still held in London untouched. They either know that it would be impossible to withdraw that gold without a major upset of the gold market or they envisage that the UK is going to join the Eurozone within the next decade.