No doubt the reason is lost in the mists of time, locked away in the mind of some long retired engineer.
I've been flying 2 dots low ever since I first went there yonks ago.
Doesn't do much for safety when breaking visual in rain at 200ft, trying not to "duck under" and land short, but still trying to hit the 1000ft markers on a wet runway.
The preliminary report on the recent B737 excursion at DN in interesting reading on the Departments website.
Investigators are currently asking 737 pilots using Darwin recently to provide information on their experiences on a no blame basis. Must be something there they are trying to come to terms with, and looking for some honest opinions.