I know this isn't very timely, but we've updated our lesson on early decision with more information about who it helps and how much.

This is the relevant section: How much ED helps depends on where your LSAT scores and GPA lie relative to the school’s medians. Our data show that if your LSAT and GPA are both stronger or both weaker than the school’s, ED doesn’t give you a measurable boost. Applying early decision helps most for splitters: candidates who have one number (LSAT or GPA) at or above a school’s median and the other below.

Full lesson here: https://classic.7sage.com/admissions/lesson/apply-law-school-early-decision/