The tasks are arranged so as to try and make sense of them. For example, in the text, it talks of one dog, then a leash, then a leash for two dogs, then two dogs. The hierarchy of the list shows which tasks have to be done for other tasks to be completed. There are three tasks done that aren't listed by Ysbaddaden: the getting of the pups of Rhymhi; the getting of the dogs of Glythvyr Ledewig (though either of these could be task 36 - the getting of Aned and Aethlem); and the getting of Gwrgi Severi.