The function works the way it’s supposed to, like I said, as long as there isn’t any errors. I’m not having any issues with ACF working correctly. I think you’re going down the wrong path by trying to figure out what ACF is doing.
To answer your questions, the load_value() method in each field class does what it needs to do base on the field type. The post object fields for examples returns a post ID, or an array or post IDs if something is saved or it returns flash if nothing is saved. On the other hand the taxonomy field has a lot more work to do. All of the functions in ACF are real function, they all do something.
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