Like richardfm I too have been baking bread for years and have never used ascorbic acid (vitamin C), not even in a 100% wholemeal dough.
It’s one of the tricks* that commercial bread producers use to make loaves and isn’t necessary.
Be wary of using it in tablet form as these contain other things such as binders that might adversely affect the bread. You can buy it in unadulterated powder form for baking but it’s an unnecessary expense.
It won’t be needed in the smallest loaf as that is such a small quantity of dough that it doesn’t require the gluten-strengthening effect of the additive.
*”The net result of AA is to improve the ability of dough to retain gas (as seen by increased oven spring) and to yield bread with a finer (smaller average cell size) crumb cell structure. These changes also result in bread crumb that is softer to the touch yet has the resiliency to recover much of its original shape after compression. This helps to convey the impression of proved freshness to the consumer.’“
Baking Problems Solved, p 55, S. Cauvain & L. Young, Woodhead Publishing (2001)