Top Law Schools

Naturally, the closer your GPA is to 4.0 the lower LSAT score requirement. Likewise, the closer you are to 3.0, the greater the need to score higher. Therefore the point of diminishing returns will fluctuate. Generally speaking score(s) tend to be the point of diminishing returns? (i.e. benefit of scoring a 178 as opposed to a 173 appears to be much smaller compared to a 173 as opposed to a 168).

These numbers are not precise. Although aren't score tiers going to look something like this :

I. 173+
II. 170-172
III. 166-169
IV. 161-165

I think once you're above a school's 75th percentile, it's pretty much irrelevant

It depends on what your goals are. If you're aiming for scholarship money, then those extra points beyond a school's 75th percentile scores are valuable, potentially even necessary if you're chasing a particular scholarship.