The volume of any loaf has great impact because it is the first thing to be noticed by an appraising eye. Nobody is attracted to a small or heavy loaf. On the other hand, a discerning customer or guest will be put off by an overblown and blousy loaf that has a structure that is too open. That overblown loaf will soon dry out, and for most people its open structure will not be a satisfactory vehicle for butter, toppings, or fillings.
An exception would be a bread like ciabatta, seen in the next picture. Its open structure is the very nature of the bread, and a tight crumb would be a failed version of it.
Imagine that ciabatta structure, with its open random bubble, being a sandwich loaf. A travesty, with honey all over the plate, or mayonnaise on your shoe. Hence the sandwich loaf maker must not only drive gas pockets from the dough, but also keep a tight rein on final proof to keep the uniform and consistent bubble suitable for toast or sandwich.
Any discussion of volume has to begin with the dough. To make good bread the bulk dough itself must achieve a satisfactory volume, it must be left to gas and rise. See the picture here where the soggy surface of the fully-proved dough leaves a distinct hole when the floury finger is inserted deep into it. Like the test shown at the top of this post, a poke with an outstretched finger is not to quickly close up, which happens when the gluten is still unripe.
To summarise, there must be proper volume in both the bulk dough, and the resting dough before it is shaped. Then the baker must judge the final proof so that the loaf springs in the oven and gives satisfactory volume to the final product. See the loaf in the next picture, a stoneground white high tin. Notice that when the volume is right, everything else looks right: lovely crust colour, handsome rip along the loaf’s length where the oven spring has torn it, overall proportions look right.
Oven spring can be viewed as the final accolade for the baker. When proof is right, volume is right, and you pop it into the oven when it has sufficient life to give a little spurt that results in handsome oven spring. For breads that get slashed, the oven spring opens out the cuts.
Now see a loaf that went into the oven a bit early. It was a sourdough loaf made with heritage wheat and thus had feeble and delicate gluten when compared with modern flour. Fearing it may collapse with the impact of sliding it off the peel onto the oven tiles, I made my misjudgment that led to an oven spring that was gross. A few slashes would have helped release that spring.
Now you have the full picture. There will not be satisfactory volume in a finished loaf unless there was satisfactory volume along the way – in bulk dough after its first rise, in resting dough pieces, and in final proof. To achieve correct volume of any loaf the gluten has been fully developed (ripened, “conditioned”), with good judgment of final proof, and with adequate gassing power at the time it is placed in an oven holding the right temperature.
Good baking, Paul