Divergence is possible but not certain? Without divergence from the rules and regulations of the EU, what is the point of Brexit? Having control, but never exercising it, for example, would make the whole fandango even madder.
At present we are not 'permitted' to diverge from the EU plans.
Regaining the right to choose whether to diverge (or not) puts us back in control of our own future, and free to diverge if we wish. However, I am fairly sure we will diverge once we no longer need to align ourselves with import tariffs intended to protect markets in which we are not major suppliers (such as wine). This does not mean we will have to divulge in all areas.
The comment about 'making the whole fandango even madder' suggests that you believe that the majority of the voting public have made a 'mad' decision. Clearly you do not believe in democracy. The 'remain' voters can hardly claim to be the only sane group in the UK. If their vote was based on the forecasts made by the remain campaign, then their views have already been proved to be false. How much longer will remainers continue to claim we're "going to hell in a handcart"? We were told (by the remain campaign) that voting to leave would cause immediate job losses in the hundreds of thousands, and a 'massive' black hole in the budget. have you not yet noticed that this didn't happen?
Why do you assume that the current prophesies of major calamity (if we eventually leave) are accurate, based on past performance?