'Err not so much oil - any that does might stay in Scotland should that leave. The remaining coal we have is too expensive to mine, and anyway we shouldn't be using fossil fuels any longer.
The rivers would need a hell of a lot of investment to get them up to speed in providing hydroelectric power. And an awful lot of time. If it were even possible.
Finance - well we need the passporting to continue and already companies are making noises about moving their offices out of the country.'
This is the kind of post I absolutely expected in response to mine and, like all good arguments, it is at least founded on truth. Oil is running out and, at current prices, a lot of it is not exploitable. However, increasing technology is allowing us to access more oil at lower cost. In addition, it is unlikely that oil will stay this cheap for very long. Coal is a long term resource and will, at some point, be economical again (unless alternatives become much cheaper). As for Scotland getting the oil, firstly I think it very unlikely they will ever become independent and, secondly, it is debatable legally to whom the oil belongs.
As for our universities, the kudos of studying at Cambridge, Oxford, Imperial and, to a lesser extent LSE and others, will remain. They are struggling financially against the two or three top ivy league unis but there are no European universities in serious competition with them. They are global hubs of learning and no Brexit deal would stop the best and brightest globally from coming to study there.
As for the City and passporting. Yes, some jobs will go but these are most likely to be back office (and maybe some middle office). There is no desire amongst the top earners to relocate from a global city to Paris, Frankfurt or Brussels, particularly as there is not one clear alternative and it would mean spreading out in a geographically diversified way across Europe. The City and Wall Street also have some of the best oiled lobby machines in the world and I am confident on this basis that the City will retain the vast majority of what it does now (and please don't quote me about people saying that they are going to leave, that is all part of the lobbying process).
Momentum and inertia play a huge role in decision making and the idea that huge chunks of the economy will decamp to Europe I just find highly unlikely (as per the threats before the 50% tax rate and the actual number of moves after it).
We are not a tin pot economy. We are not a superpower (clearly) any more but the idea that we have nothing without membership (as opposed to access to) the single market is also a very exaggerated and negative perspective.