I am beginning to think that the significant difference is that with songlines, learning is always done in the physical ‘memory palace’ which is constantly revisited. It can be recalled from memory, but is encoded in place. For me, that is way more effective, but I have aphantasia and very poor visualisation, so it may not be as big a factor for others. So recalling your childhood home can be a memory palace, but not a songline.
Lynne Kelly is correct here that we need better delineations of the words we're using here.
To some of us, we're taking historical methods and expanding them into larger super sets based on our personal experiences. I've read enough of Kelly's work and her personal experiences on her website (and that of many others) that I better understand the shorthand she uses when she describes pieces.
Even in the literature throughout the middle ages and the Renaissance we see this same sort of picking and choosing of methods in descriptions of various texts. Some will choose to focus on one or two keys, which seemed to work for them, but they'd leave out the others which means that subsequent generations would miss out on the lost bits and pieces.
Having a larger superset of methods to choose from as well as encouraging further explorations is certainly desired.
