Let's take the case for 5 Kg of Briess 2-Row Brewers malt, and the extant data from researcher #1 and researcher #2:
For researcher #1:
(6-5.4) = mEq's_acid_base/(57.2 x 5)
0.6 = mEq's_acid_base/(286)
mEq's_acid_base = 171.6
For a mash pH target of 5.40, and given that at that pH the mEq's of acid contained within 1 mL of 88% Lactic Acid = 11.451, we get:
171.6/11.451 = 14.896 mL's of added 88% Lactic Acid to move this mash to pH 5.40
And now for researcher #2:
(5.55-5.4) = mEq's_acid_base/(46.2 x 5)
0.15 = mEq's_acid_base/(231)
mEq's_acid_base = 34.65
For a mash pH target of 5.40, and given that at that pH the mEq's of acid contained within 1 mL of 88% Lactic Acid = 11.451, we get:
34.65/11.451 = 3.03 mL's of added 88% Lactic Acid to move this mash to pH 5.40
14.9 mL's of 88% LA required for researcher #1's data vs. 3.03 mL's for researcher #2's data.
This is how bad the data gathered by D. Mark Riffe is for this malt. If you plot the computed mEq's for both vs. the nominal color of this malt, that is clearly a whopper load of chart scatter.
So if we are mashing 5 Kg. of this Malt in DI water, do we add 15 mL of Lactic Acid, or do we add 3 mL of Lactic Acid? Or should we split the difference, and add 9 mL of Lactic Acid? Or should we apply bias and cherry-pick the data?
As an aside, titrations like this are generally carried out using pulverized malt whereby to liberate all of the malts inherent mEq's of acid or base (with basic meaning with respect to the targeted mash pH). But the typical LHBS gives you malt crushed through a mill gap of about 0.039". Should one's software presume that 100% of the malts inherent mEq's of acid or base (with basic meaning with respect to the targeted mash pH) will be liberated for the case of the 0.039" mill gap? Or should the software compensate for less saturation during the mash and thereby conclude that a bit less acid or base will likely be required whereby to move the poorly crushed malt to the desired target pH during the mash? We already know that the yield of sugars from the poorly crushed malt(s) will result in a low OG. This seems to imply that the mash water is not reaching some portion of the malt. And thereby failing to liberate the acid/base as well as the sugars.