Maybe it's robust _because_ it was built in 1999, where nobody felt an obligation to add fancy scripts to a text document ;-)
(The current trend of font size inflation is incredibly frustrating because it makes it impossible to configure a browser such that old and new sites are both readable; I have to blame it partly on designers with large screens not setting their DPI appropriately and partly on web browsers not adjusting their default stylesheets for modern screen sizes)
It's incomprehensible to the layman because there is an extreme economy of transmitted data. To decode it you have to know a fairly large vocabulary of domain specific symbols and do some computations to retrieve the correct wind speed and direction, which are encoded.
This is so you can always get your weather, one byte at a time if needed.
KDEN 101353Z 33009KT 10SM FEW080 FEW180 FEW220 04/M09 A2985 RMK AO2 SLP079 T00441089