Re: Downsides to flat-bottomed skiffs?
Dories predate stacking on deck by centuries. Earliest evidence goes back to the 1300's. Seem to have come along when sawmills started happening so wide boards could be produced. Have a look at the first chapter of the Dory Book. Some of these dory built boats are quite wide bottom e.g. Arnold's bateaus. Might be better to think of dory as a construction method that involves lining up some planks, putting cleats across to hold them then putting sides on with crooks to hold them. One could see how this could be developed out of rafts, whereas cross planking with short stuff was a way of repairing a dugout bottom and we have hard evidence that this was the case.
Ran Tan, Liten Kuhling, Vernon Langille, Josef W., Merry Mouth, Imp, Macavity and a quiver of unamed 'yaks.
"Bound fast is boatless man."