Thems Fighting Words
Green Belt
I noticed that there are not to many double edged blades in the Philippines. And from what i know about the rest of the SE Asian area, I don't see many double edged knives there either. there are some but not as many that are single edged. Many of the swords have some sort of edge on the spine for certain strategic purposes but not so much the knives. Hmmm, I wonder why that is.
Most short blades are better as stabbing weapons as far as damage capability is concerned because the cutting surface is too short for slicing or hacking. To increase cutting surface, many double edged blades are waved to some extent such as the Kris and Kalis. Curving a blade (with a single edge) is another way to increase cutting surface, such as with a kukri. Here's a site with some nice pics of the variety of short blades employed in FMA. I have no knowledge of the school (so don't ask me questions about it)< but the pics are pretty nice.
http://www.marcialtirada.net/traditional_filipino_weapons