Think you're reading a bit more into a single line in my post than is warranted.
First of all, I don't see what grandmas have to do with anything. Since when has age mattered at all with this sort of work? Rather, in my very folk based tradition, one might expect to find what is most efficient for them ebb and flow with different times of life, as well as with practice and with the season, year, etc? Besides, how do you know I'm not a grandma?!
Second, imagining alone is going to get you horse manure. Body visualization still requires energy, used in very specific ways, and they are not ways especially efficient or useful for me, probably because of significant body trauma in my past that I am still slowly healing/learning to work around. In contrast, connecting and working with spirits is very nearly effortless for me, and requires very different kinds of energy manipulation.
Finally, I said I sucked at it. Not the same thing as having "trouble" or "issues" with it. I suck at math, too, but I don't have trouble balancing my checkbook. It simply takes me longer, takes more effort, and is better done with tools to help me, so I don't make stupid mistakes. Same thing here; pulling from the universe, as Miller, Burce, and others advocate, takes more effort for me than I get back for it, particularly compared to a smaller, more organic, more localized, and more focused sources of energy, even when I do access them in similar ways.
One size fits all approaches to magic make me crazy. As I've said elsewhere, this idea that "what's easy for me is easy for everyone" is not only damaging to the study and practice of the occult as a whole, it's as silly a concept as it is in mundane education and it is, in a word, WRONG.
Finally, because I might as well finish this properly: seriously?! As occultists, witches, magicians, whatever else we all call ourselves, doing what we do... you really, honestly, actually expect, much less advocate, anyone do anything the way everyone else is doing it?!