Let's say you are smart crafting a focuser, and you currently don't have enough alloy so the smart crafter is crafting alloy. Now you switch to crafting a booster. The current alloy is restarted.
This is dumb, not smart.
Expected behaviour: Smart crafter should never restart an ingredient. Ideally it would wait to finish whatever is being produced so long as it is an ingredient (or child ingredient) of the recipe, before following its usual algorithm.
Alternatively this could be the default behaviour for all crafting, or an option: finish the current item before starting to craft your selection.
EDIT: Or even better, just remember crafting progress for everything.