Cunning thing midges. As reported in BG!'s blog, with a report from The Scotsman, scientists were going to be testing a midge spray that would cloak the wearer from the wee pests. A big test was run at the weekend's Loch Ness charity run. According to the Press & Journal, "midges were strangely rare" during the event.
Maybe it is like that elephant deterrent I bought for my flat.
Hopefully the scientists glean some useful data.