When you download this zip file, it contains three custom tone curves: the +0.3, the +0.5, and the +0.7 curve. The author - whoever that is at the moment - had recommended that overall picture taking would be best with the 0.5 curve.
So I uploaded the +0.5 curve and tried it out. It definitely does a good job of bringing up the midtones without blowing out highlights. It made a noticeable difference in many of the photos I've taken so far.
I don't know of the specific curve you are talking about so I can't make comparisons.