Help me understand: MT-G2 and the MacAdams Step ratings

I've been looking at the Eagletac MX25L3 MT-G2 version. It has a 5000K LED and thinking that I might prefer something a bit more neutral I started looking into replacement options.

On Cutter's website I found a slew of possible options. https://www.cutter.com.au/products.php?cat=Cree+MTG-2 I see that there are 6, 9 and 36 volt versions of the LED (I would assume that the Eagletac uses either the 6 or 9 - but would need to measure that).

The part that confuses me are the 2-step and 4-step MacAdams ratings on the LEDs.

From this article http://assets.sylvania.com/assets/documents/faq0026-0999.f4172b60-cde8-4cb2-8a0a-37d3490d9e49.pdf I can deduce it has something to with color output variance over standard deviations - but I am not sure what those deviations mean. Is a lower 2-step number better than a 4-step number?

Any information would be great. These LEDs are $20 each so ordering the wrong one has a bit more impact than ordering the wrong XP-G2.

Take a look at Page 12 of 18 in the datasheet. The line through the middle is the Planckian locus. Go above that line, tint gets green. Go below it, tint gets pink. Stay on it and the tint is pure white.

2-Step tries to keep you bang on that line. If you buy 100 LED's in 2-Step binning, they should all appear to be the same tint when you line them up side-by-side and look at them.
3 or 4-Step allows variation from that line. So some of your 100 LED's might be greenish and some might be pinkish and some might be true neutral.

2-Step is better since you're less likely to get green/pink tint. Probably costs more as a result.

I always wondered what the meant, too. What I noticed about the SX25L3 I had is that the tint was almost the same from the hotspot, corona, and spill. The Nichia 219 hi CRI lights I have all have a consistent tint throughout the beam, too. What I did not like about the SX25L3 is that the 5000K tint was a little too cool for me. I would have liked the MT-G2 to be 4300K instead but nobody is offering that option.

Thanks for the explanation calipsoii. I can almost understand that.