Thanks for the invite to join in! My take:
1) The nice thing about the GMAT is that you don't have to thoroughly understand all the rules of English (otherwise I'd certainly be out of a job), but rather just the application of what's tested. I think niksworth's point is a phenomenal one - "as long as it conveyed proper sense". If the modifier is logical in what it modifies, that's a much better general-case rule than trying to build an if-then flowchart that accounts for every case.
2) When a modifier includes a modifier, the appositive PHRASE needs to modify the word that comes next to it, but the words don't necessarily have to "touch":
The most popular girl in school, Marisa is captain of the softball team.
"in school" is kind of a necessary modifier...without it it's pretty nebulous how popular Marisa is (most popular in the world?). But using it pretty much dictates that it's going to separate "girl" from "Marisa". That's okay...the phrase is directly adjacent to her, so we know that it modifies her.
Again, the nice thing with the GMAT is that you always have choices to make between multiple options, so you don't have to know exactly what's right as long as you can recognize what's wrong. When in doubt, see if you can fall back on logic (does it make sense?) and that can be your guide through unclear situations.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
Looking for GMAT practice questions? Try out the Veritas Prep Question Bank.
Learn More.