The sudden rise of gold price would certainly be perceived negatively in terms of the broader economy especialy above and beyond $1000 . As we we know the ECB and FED's main purpose is to maintain economic stability and contain from now on inflation .
The rise of gold would be perceived as an indication of failure of those policies from private investors , so it's very possible that such and understanding between China and the US UK AND ECB has been made to gratify China with the sale of the IMF gold reserve while keeping the prices down by avoiding overbidding .
I personaly think what happened behind the scene at the G20 between central banks had more clout then what was said in the forefront .
Tec