The 1000 card tells me what the querent 'would have asked about' while the 3-Line of Lenormand cards is the reading within that question's scope (or part of their life) if it were true reading."
So she's using her Deck of 1000 Spreads to help her hone her Lenormand skills! And she goes on to stay that, because Lenormand is linguistically based, it's a language meant to be spoken aloud to the client. So she does her practice readings aloud to measure the quality of her wording and "veracity of the message."
Personally I feel that reading aloud is not just a great idea, but also a great way to learn. It hadn't occurred to me to do it when practicing or reading for myself, but it's something I'm likely to try. I find that when I read for a querent, the act of speaking itself starts sorting out meaning. Then as that happens, ideas pop into my head, more so than when I just read inside my head. Certainly when I journal a reading, as I often do for my own self readings, I find I get greater insights based solely on the more detailed train of thought that comes from writing things down, rather than just glancing at the cards and determining a quick answer (as I sometimes do when reading myself.)