Hello!
That's a very interesting theory, with the big problem being how the transition took place between the bronze age sword and the flyssa. How des one get from a double-edged blade to a single edged? Maybe the similarity is purely aesthetic, and maybe there is domething to it. The same problem applies to the yataghan/flyssa relationship, where, as Jim noted, there is a bit of a gap in documentation.
As Andrew suggested
check out the Big Flyssa Thread, it contains all the discussions ( I think) about these fantastic weapons.
I have some crazy theory of my own, but it's way too insane to present at this moment
Also, this topic gets me passionate and I end up ranting a lot...so I'll stop now.
Emanuel