Re: More FUD
I disagree. Ireland exports more to the UK than anywhere else, and if Sterling continues to trend back down, UK importers will be less able to afford our goods, seriously impacting a major market. Unlike FDI, this mostly hits the more loyal and inwards investing local businesses. You assume the rate will remain unchanged, but already the GBP gains in 2015 have already evaporated over Brexit fears, with risk of falling as low as 1:1 parity predicted:
http://www.xe.com/currencycharts/?from=GBP&to=EUR&view=5Y
You refer to a shared currency - the Irish pound ran at different values from 1210 to 1801, at which point military control of the island of Ireland was mostly complete. By 1826, the UK moved Ireland onto the UK pound. Once the Free State was created in 1922, Sterling was retained until 1928, at which point a seperate currency was created, but using the same gold ratio, it was artificially pegged to the value of sterling, which compensated for the damage done by the churlish embargo and financial disruption approach taken by the Empire. Eventually the goods which could no longer be taken by force needed to be traded, which thawed this somewhat, and by the 70s, Ireland entered the EMS, breaking the pegging in 1979. So essentially largely seperate except when under direct military control, and even the pegging stopped 37 years ago. Not exactly a current review of things there...
Irish/UK free travel is currently granted under European agreements, and for this I have no doubt than the 2 years lead in would allow time for us to negotiate similar for mutual benefit - or else the border will be very difficult. Interesting times for the already expensive to maintain North ahead as well.
I'd be wary of anti-FUD FUD, when you should at least consider the facts first. I agree that much of it will right-size within 5 years because life goes on no matter what, and it will certainly not be truly calamitous, but it will move cost jobs, trade, and relocate businesses. In the UK and outside, we will be dealing with areas of increased unemployment and government dissatisfaction, trade challenges, and legal agreements being renegotiated. It does sometimes feel like the Brexit arguments are all emotive.
But hey, Trump has your back now, so it'll all be fine!