Ibrahiim, what Spiral is saying is that the Ingrams quote simply states "swords", not what kind or shaped swords or whether or not they were stiff or flexible blades. Your conclusion is therefore an
inference based upon what you know of the Razha sword dance, though i am not certain that it stands as
proof that the type of sword other are claiming here does not exist.
Here is a link to an entry on the Razha which does indeed seem to support that this dance is performed with flexible blades, though there is nothing here about the origins of the dance itself or what swords may or may not have been used the very first or subsequent times it was performed. Just as Morris sword dancing is done with dulled blades made specifically for the dance it does seem likely to me that when this dance was first created it was done to some extent with true combat blades.
http://www.jstor.org/discover/10.230...21104396533277