Hey TB - I can certainly try!
Those are all extremely broad ideas, particularly the last about attractive wrong answers, but maybe if I elaborate on each a bit they'll make more sense.
The idea of avoiding false assumptions about the stimulus is a very generalized notion, but usually, or at least quite often, it relates to people applying real-world knowledge to the topic at hand, and thereby adding details or beliefs that may not be true in the LSAT World that the stimulus represents. This same issue arises at times in Reading Comp, where someone familiar with a passage topic will begin to read it through their own experiences or pre-existing knowledge that may or may not apply to what an author is trying to convey. I remember a course student years ago getting really hung up on a particular LR question because it dealt with a regional bank branch and something along the lines of how the tellers (the people behind the counter) behave/operate. The student's struggles arose because she just happened to be a bank manager at the time, and assured me repeatedly that what was described in the question was in no way reflective of the real world ("no bank would ever operate like this! It's totally wrong!"). But as a Must Be True question we simply had to accept the "facts" as given and then use them to draw an inference, regardless of what they're actually describing! Once she got her head around that everything was fine, but it reminded me not to impart outside knowledge to LSAT content! Simply read and react.
Misdirection is obviously another enormous concept—anything that distracts you or confuses you or gets you to misread or focus on the wrong thing could be called "misdirection"—but I'd say it's most commonly associated with Shell Game type answers. These are answers where you encounter content that is close to what you read in the stimulus, but different enough so as not to be relevant. You see them a lot in Must questions, but they can appear anywhere and cause issues. One that comes to mind was a Must question about students learning to interpret different handwriting (I'm paraphrasing) and how that works, and then a tricky wrong answer was about students learning to write in different styles. The stimulus was reading, the wrong answer was writing...but it gave people fits. That's why reading extremely closely/precisely is so critical!
As for the third, attractive wrong answers...where to begin? I mean, answers can be attractive for any number of problematic reasons—that's basically the source of the entire test's difficulty, after all—including the two mentioned above, so I'm not really sure what to say on this beyond a central truth: answers are always wrong for defensible reasons in the eyes of the test makers, so as you practice and review don't just seek out the right answer; always, ALWAYS determine valid reasons for eliminating the other four! The better you get at dismissing answers (for whatever reasons they happen to fail) the more successful you become, particularly on the hardest questions where this type of scrutiny and skepticism makes all the difference!
I hope that helps!
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