RE:what if physical delivery is cause of falling etf gold hoardDefinitely a possibility ! Also important not to forget the Basel III framework for banks which (for the first time) allows them to hold physical Gold and use 100% of its valuation towards capital. This to me has always been what's pushed Gold prices higher, that and continued central bank buying.
As for TUO I see some games being played between certain houses. Something going on in the background, bullish for TUO, but the players aren't ready to let the cat out of the bag just yet, so strong bids get their wrist slapped as the manoeuvres continue.