Most of the time, the Prime Minister does an excellent impression of cluelessness, combined with an ability to believe that dead horses are in fact full of vigour.  Like the shopkeeper in the famous Monty Python sketch, she stubbornly insists that the horse is either sleeping or temporarily stunned.  No matter how many different people point out with varying degrees of anger that the horse has indeed gone to meet its maker, she continues to argue that it merely needs the right encouragement to return to life.
And then, just occasionally, and apparently by accident, she stumbles upon an obvious truth, and comes out with an entirely sensible statement.  Responding to a question from POLITICO this week, she said “Just think about this: If having those EU regulations stopped good trade deals, how come the EU has done trade deals with countries around the rest of the world?â€�.  It’s a remarkably astute question which goes to the heart of the ridiculous assertion by the Brexiteers that the EU stands between the UK and trade with the rest of the world.  In fact, the UK benefits from a huge range of trade deals negotiated by the EU on behalf of all its member states, leveraging the sheer size of the EU market to obtain more favourable terms than any one country would obtain acting alone. 
This flash of insight was short-lived however.  Having so easily demolished one of the key arguments of the Brexiteers, instead of going on to ask the obvious supplementary (‘So why are we doing this?’), she reverted to flogging the dead horse by repeating the mantra that we can have both frictionless trade with the EU and opt out of the single market in order to duplicate the trade deals which the EU is doing anyway.  Darkness returned.