I always delete the 'My Clippings.txt,' after having 100s of pieces on the device, I don't think it's the best way to get my notes and highlights. If I understand you correctly, this is how I should proceed:
I keep a mirror of my 'documents' folder of my Kindle on my computer. In case my Kindle dies, gets lost or stolen, I borrow a clean Kindle from a friend for a day (this is possible), copy my documents folder onto that Kindle, attach an Amazon account, upload everything to the Kindle Cloud (Is that possible?
This page doesn't mention I can sync from a Kindle device to the Kindle Could). Then, I will have access to my documents, notes, and highlights, from Kindle Cloud Reader, and the Kindle iOS and Android apps, on whichever device I sync my Kindle Could. Is my understanding correct? Thanks.