The general belief is that some parties within the EU intend make this as difficult as possible, as a warning to other future countries trying to exit. The trade portion of this alone, will likely fail, and I suspect they will exit without an agreement in the end.
You have to look ahead. France will likely be run progressive Macron, and Germany by Schulz (not Merkel) by the end of this year. It will be an EU for the next four years dominated by the far left. That alone, will hinder any positive agreement for the UK in the end.
Oh, I’m looking ahead. The last country with any assests still in the EU will be left holding the bag. If the Brits have any brains, they’ll hit ludicrous speed on their way outta the EU.
I just read Article 50. The 2 year time period is not obligatory. The article just specifies that exit will occur after 2 years. Looks to me like the Brits could bug sooner rather than later. So why bug later, eh?