mk,
your date argument (1964) pretty much makes sd look completely bogus. However, you need to consider the syncretic nature of indonesia. The indonesians as a culture are highly adaptive, and sometimes a superficial change is adequate to satisfy most as a change. The laws against cma and chinese language also require indonesian citizens of chinese decent to have indonesian names. The adoption of bahasa indonesia required the generic chinese term in indonesia (kun tao) be replaced with a bahasa word (silat). Which is why you see cma called 'silat' even though it isn't 'silat' in the specific sense.
It was also common to see blending of cma, jma, and ima in certain circles, because there were strong traditions of holding back (see draegers "weapons and fighting arts of the indonesian archipelago") - it is possible that this is the root of sd. But i doubt it based upon the technical skills i've seen from sd people.
All this aside, i'm convinced that sd is a fraud perpetrated by sin the'. He is either a jovial con man whose great conditioning and decent karate skills allowed him to con unknowing americans, or he's the biggest freaking idiot in the world and actually beleives his own stories. In either case, why would you want to follow him?
The footage of him moving was the clincher. While i have seen kun tao players do, say a mantis set that was obviously made up based on something else, it still had the content of that something else. Sd just looks bad to me.
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