Hmmm... interesting. I'm doing All About Spelling with DD9 (dyslexic, ADHD-I) and see your original pattern: she remembers the gory details of the rules (in so far as they exist - argh!) much better with individual words, and tends to lose them with sentences. I wonder, though - could it be an ADHD effect kicking in? Does your wonderful OG teacher maybe provide such interesting sentences that they are easier to keep attention focused on? DD's psych testing showed a pattern of much higher scores on "meaningful" memory and processing tasks as opposed to those without content, and we definitely see that in real life, too.