During my research into the history of Krabi Krabong in Thailand there is very little information, especially regarding the development in Northern Thailand.
One thing I have uncovered is very interesting in that during the 19th Century Temples were places that taught a great many things and swordsmanship was one of the things taught. This was due to the fact that many ex soldiers took to the robes to gain merit for the harm they had done on the battlefield and still passed their skills on to the next generation to help them protect their families and villages and also to prepare them for war.
First the practitioner would be taught meditation, Samadhi to help concentration and discipline the mind for the training to come, the Wat was a perfect place with no outward distractions.
Unfortunately I believe many of these schools died out when the Abbot or monks who were teaching passed away, but it partly explains how the art survived and evolved.
It is interesting to note that the events are similar to the Shaolin temple in that warrior monks trained in fighting arts and Buddhism, but the main difference in Thailand is the monks were just, that they had renounced the warriors path and taught to help preserve and protect.
Nowadays this art has become more of a folk art and more of a dance than martial art.
It is usually performed with two swords smaller than the ones we use for Krabi Krabong.
For those of us that understand the warrior arts of Thailand it is easy to see where the martial techniques are hidden and I visited a master of the Fon Daab, Ajarn Gao Wai who is 78 yrs old and studied since he was 12yrs old and in his time he never learned the martial art side of the Fon Daab.
With the help of my Krabi Krabong teachers and my own research I have discovered that the Lanna Daab is the length of the fingers to elbow. Because the blades are shorter they were used more for medium to close range, attacking vital points and arteries.The footwork is more like Kung Fu with many twisting stances to avoid attacks and no direct blocks just parries due to lightness of the blades.
If the warrior lost his blades then he would employ empty hands similar to Muay Boraan, but would also use clawing techniques to incapacitate an opponent.
As in all martial arts it is the mindset that makes the Thai Warrior special I believe this stems from the culture and heritage.
It is a shame we can no longer learn this art as it was originally taught for the battlefield, but through people like Ajarn Gao Wai it will continue to be part of the Northern Thai culture and a link to the Lanna Kingdom.