Frank - the rules around Govt tenders being written and publicised give failed bidders opportunity to sue when a Govt body makes a mistake or is seen to discriminate unfairly between private companies. Perhaps listing Heathrow as a valid option of London airport is nothing more than an a**e-covering exercise in this regard so as to prove Dundee is following Govt procedures strictly, or at least can claim a defence against discrimination in a potential litigation outcome ?
Interesting point, makes sense!