Do you read Chinese? I do. The examples given in the paper involve forgetting which radicals constitute a character. It very much feels similar to forgetting whether it is “through” or “thru”. They put the wrong component down. They did not forget how to write the set of components in common use.

There are cases, almost certainly overrepresented here, where a character has some truly unique variation that the writer forgets. They know it is different but forget how. In almost all other instances it is a matter of forgetting “is it heart or fire here?” as these two are very similar. It’s like spelling with an i instead of an e.