Yes in theory that would work....and even sounds like the best solution. But the hull is going to change shape slightly and you'll have to handle the deck and hull pretty roughly to get it all lined up. You'll probably do a few test fits. During this lineing up process, it's very possible you'll damage the cove edges, folding some edges inward and breaking some off.
I should clarify I'm talking about building on an external strongback where the deck and hull become separated. Building on an internal strongback may change things entirely.
In the pic below, there was a lot of clashing and knashing to get the halves together. A cove edge would have been beat to he:: in the process.
Ian

: Why flatten the edge at all? Why not leave a bead (or cove) there?
: Of course, you'd have to leave a mating edge (bead/cove) on the
: deck strip for when you join
: deck-to-hull.