Hello John,
Well, I'd suggest that Marsden's account got heavily tinted by the colonial perspective of those times: Get your soldiers killed outside the battlefield (surprise, surprise for any occupying army!) and it's regarded as an assassination; have your soldiers killing some non-collaborating locals and it becomes a heroic deed...
However, I still find myself wondering about Leigh's assertion that sewar were reserved for nobility. It seems well established that rencong basically took the place of keris in Acehnese culture. This is supported by their huge diversity (decoration, pamor, size, fittings, etc.) suggesting that just about every member of the culture was wearing at least one.
I observe the same (or an even higher) diversity among sewar though. Moreover, the use of sewar seems to be much more widespread on Sumatra than that of rencong... Quite a few sewar originate from the Minang Kabau and I've never heard that they were a sign of nobility/rule there (also their often moderate decoration and the high status of keris seem to speak against such a notion). If correct at all, were sewar possibly restricted to nobility/judges only within the Aceh court (and other sultanates under its rule)? OTOH, any well-provenanced examples from the Aceh sultanate with plain original fittings which would point towards use by commoners?
Regards,
Kai