Well I ended up happy with my call not to take the long entry off the top of that EU 12h hammer yesterday. I've taken a look at the structure of the 60m level to see why price broke down overnight:
The above shows why I typically place both long & short orders on Hammers & Shooting Stars because often if it doesn't initiate a reversal price ends up doubling back on itself within the following candle & go the other way.