Thornbury is as big a clown as Abbot. She has regularly made an absolute bell end of herself on question time, perhaps most memorably her announcement that Labour would seek a 'deal' from the EU, bring it back to the country and then campaign against it
That policy - put forward as 'pragmatic and democratic' by Starmer and Thornberry in particular - was such a massive insult to the Labour Leave supporters.
It basically said - we want to Remain but need to say something that sounds like we are balanced. Let's adopt this policy and get a shit deal from the EU and then a Remain vote will be guaranteed - those thick northern twats won't realise what we are doing