Hello once again everybody, and thanks for your responses to my initial post. Since then, I've spent the majority of my time going through quant and am now turning to verbal (as you can tell, this clearly has taken more than 2 months to pan out...)
As mentioned above, I had V45 on my diagnostic, and got all the SC questions correct without reviewing prior to the test. That being said, I've gone through a few of the SC Butler/other questions here and definitely feel like there is room for improvement/room to minimize any randomness associated with my diagnostic score.
My problem with Sentence Correction is, on the surface, not the worst one to have. I'm a native English speaker and am able to get through a reasonable proportion of the GMAT club SC questions purely based on "ear." I bought a copy of the Manhattan SC guide and am not convinced that going through all the exercises in the guide is the most time efficient way to proceed. I'm a bit intimidated by all the grammatical jargon in the book, especially since I'm familiar with the concepts that this jargon is supposed to help explain, and I don't want to lose sight of the forest for the trees, so to speak. For example, I'm not sure I want to re-train myself to go down a list of grammatical rules crammed from a book when looking at an SC question, although I do acknowledge reading cautionary tales about how a lot of spoken/written english is, in the strictest sense, grammatically incorrect.
My current plan is the following, but I'd love to hear your thoughts/suggestions:
1) Do a sample of questions from the 700+ level SC categories on the forum and see which ones are causing me the most trouble.
2) Do a targeted review using Manhattan SC/GMAT Club grammar/any other notes you may find useful(?).
3) Do all the OG problems once I've self-diagnosed my issues and corrected for the issues I discover.
All responses are much appreciated!