Well, I think maybe I expressed myself in a not very clear way (a problem for a portoghese trying to write in english). I said “the (dataview) solution would be more obvious” for me, not your system. Because I’m unable to play with dataviewjs, my restriction to simple queries implies a way of thinking with some limitations.
For dataview is more easy to call values in cascade (top-down)
Taking your example, it’s more easy to call a value in “Subject” file, then the others comes in sequence. From one file to multiple ones: Subject → Topics → Notes
But your system take things more complicated to the query because it works in reverse way: Notes → Topics → Subject. (It’s easy to visualize the ‘problem’: in the query proposed in my last reply, the table follow the intended final order - subject / topics / notes - which is contrary to the links system implemented). With your links system it’s necessary to call in first place all the notes… but we don’t want all the notes. Then it’s necessary to filter these notes with a value in a field (“Subject”) that is not placed in these notes but in the next level (in the topics files).
In conclusion: your system is fine but the tool (or me) has some limitations! 