Can there be a deal with no transition extension?

It is perhaps appropriate that, in these far from normal times, that this BEERG Brexit Briefing is longer and more detailed than normal. The reason relates directly to the complexity of the question which I pose and then attempt to answer as comprehensively as possible: if there is no Brexit transition phase then can there be a deal? 


This is a companion discussion topic for the original entry at https://beergbrexit.blog/2020/05/04/can-there-be-deal-with-no-transition-extension/