Here is an example from Cooking for Engineers - Lemon Bars. If you scroll down to the recipe you can see it uses all-purpose flour twice and lists it two times on the left side of the table.
This makes it real hard to determine the total amount of flour needed. Maybe add another column to the left, that sums up all the ingredients, in the format you might get it at the store. Then the second column becomes the mise en plas step, where the base ingredients are divided and prepared/chopped/grated etc.
Problem is column 1 and 2 wont necesarily have ingredients on the same row...
> I think of them as 2 different nodes, 2 instances of the same type of ingredient.
But this is inconvenient during the shopping step of the process. There you want all uses of an ingredient (possibly across multiple recipes) collapsed into 1 node.
> The use case I'm solving for myself is easy lookup while I'm cooking
This is a constant source of stress for me cooking from cookbooks I otherwise like. I prefer to measure on-demand, and wish the steps would just duplicate the quantities of the ingredients "whisk in the olive oil (1/4 cup)" instead of "whisk in the olive oil" so I don't have to scan the list of ingredients and figure it out
Duplicating the nodes is also far from ideal when the reused node is not a raw ingredient but an intermediate with possibly complex dependencies itself. Duplicating the whole subtree would not be helpful.
