Burmese berserkers?! Nice. I can't even imagine how scary that was. Confrontations like that would have made the early invention of the Port-O-Pottie extremely profitable.
Double weapons had a place, and I can only guess that in the middle of a huge formation of other other soldiers wasn't it. So large armies wouldn't have bothered, I suppose. However, I'm told by other students and instructors that Krabi-Krabong (Thai weapon art) was often used to defend passages and gates with small numbers of troops (maybe even just one). That would be pretty crazy work with no protection, even if you were good. I remember the lessons of Thermopylae, but damn...
The tin and aligator armor in the "Unusual Keris" thread is extremely intriguing to me, though. Did the Nais use double weapons?
Question: why would any culture capable fo forging metal not come to the conclusion to wear it, or some other form of protection, to defeat metal weapons? The Moros did, but some other cultures seem to lack this basic insight -- or at least have their reasons for not going there.