xuraax,
The Razor is about simplifying the building and the butt strap joint is simpler than the scarf. The keel panels are flat and do not need a scarf joint. In hindsight I think the side panels will take a butt strap joint too. The curve will not be that great and the joint can probably be made of after curve is induced.
Along the same lines the chines are easier than steaming the hull to coach the ply to take the intended shape. This design is much less stressful for both the builder and the ply.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!