‘Where a party who had overstayed unlawfully and married or formed a relationship with a British citizen sought leave to remain, the “insurmountable obstacles” test as to return under the Immigration Rules was a stringent test and more demanding than a mere test of whether it would be reasonable to expect a couple to continue their family life outside the United Kingdom, although the test was also to be interpreted in a sensible and practical rather than a purely literal way.’
WLR Daily, 6th May 2015
Source: www.iclr.co.uk