I actually wonder how another independence referendum will go down 6 years later. How confident are they that everyone who voted No last time won't do so again?
Also, if they do somehow pull it off and gain independence, what exactly would they be able to offer the EU as a new member state? Their oil? It's not exactly rolling in money otherwise on its own compared to its worth in the UK. And it's deficit is currently 7x higher than the UK's. If they leave the UK, but their application to join the EU is rejected, they're well and truly farked.