My opinion is that a deal cannot be negotiated among uneven parties. Right now, the UK can either leave with no deal, or leave on the terms demanded by the EU, with no concessions whatsoever. There is no table for negotiation. It is leave or surrender. Once we leave, we are no longer the begging party asking for concessions, but the roles will be reversed. The EU does not want to lose one of their largest export markets, and will quickly change their mind about a trade deal.