I'm the author of said blog post regarding the 7xx bump, and I probably should clarify something:
I still believe that a sub-700 GMAT will raise eyebrows amongst firms unless your score is supplemented by previous consulting experience (or other similar, intensive work experience). Now, in my post I didn't mention that three critical adjustments happened that, I believe, placed me on the closed list of 2/3 of McKinsey, Bain, and BCG:
- GMAT score (bumped up from 690 to 7xx)
- Summer internship with a mid-tier consulting firm
- Cover letter refinement (which didn't matter for BCG since they didn't ask for one)
I can't say which of these exactly carried more weight, but my performance regarding closed lists improved dramatically compared to my internship recruiting.
I should also say that these weren't just friends that provided this advice: each one of them has been involved in the closed-listing and interviewing of candidates for their firms from top-tier business schools like Wharton, NYU, Columbia, Ross, and Harvard.