Well, it's not, and your post below does nothing to address what I was saying
Saying that trade is ultimately determined by consumers may be true, but misses the bigger picture. The companies that are selling need to be making a profit. If British exports become more expensive they'll face more competition from other suppliers. The sales with the lowest overheads currently are to the massive market that is geographically on our doorstep, but it does not follow that a reduction in exports of widgets, agricultural produce, medical equipment, etc to that market will automatically be picked up by exporting those same things to another market.
The cost of shipping to those other markets, the inflexibility due to shipping times, perishing of goods to reach other markets, no market for our goods, different standards and regulations for those markets.
As I said it is laughable to suggest that our current exports to the EU could be perfectly replaced with exports to other markets.
Well, if it's so laughable, can you please look in your crystal ball and let me have next weeks lottery jackpot numbers, because you obvioysly know what the future holds.
We don't know what exit negotiations will entail, we don't know what currency markets will, do and we don't know the magnitude of any changes in trade levels. We have economic models projecting a range of impacts, all based on assumptions which may or may not be correct, and many of the same models, and visionaries, have a history of being badly wrong for events out of the ordinary, and not a few of whom were firm advocates of joining the euro with predictions of economic armageddon if we didn't, though miraculously, they seem to be very shy about that opinion now. Wonder why?
What's truly laughable is that you think you know the future well enough to be certain that we cannot possibly expand trade with the 6.5bn people not in EU sufficiently to cover any changes in costs at the margins of trade with the 0.5m (well, less if we leave) that are. Bear in mind that those not in the EU include the growth economies while the EU is stagnating, it includes the US, India, China, all of South America, the entire Pacific region and even those sections of Africa that are growing or showing signs of doing so, not least due to enormous levels of Chinese spending.
But of course, it's "laughable" that we could do perfectly well by trading with the EU from the outside, and that increased costs of trading to the EU are mitigated by decreased costs of trading with everybody else once we, too, are outside the EU customs barriers.