In that case, if one only takes into account sides that have outer-bread crust, and do not account for the length of the sliced side, then the length would be identical in either case, and would be equal to 2 * s, whether the cut was diagonal or straight.
Doesn't matter. Not corner-to-corner, but cut on a bias.
One skinny end for dippin.
One fat end for holding, and for swabbin the deck.
Bang for buck,
Form equals function.
End of story.