Everything was exactly the same for each batch including temps and carbonation levels.
I read the article, but remain skeptical - only because brewers have been dry hopping for hundreds of years and suddenly, just now observe that 1 day is adequate. That said - the world was flat back then too...
Kharper, did you adjust the short hop schedule to finish at the same time as the longer? I am wondering about the contact time with the yeast and changes there that MAY make a difference. Stan H talks about how yeast and hops interact briefly in his book on Hops. I suspect that the longer but limited contact time (looking at real cask ale) is beneficial in refining the hop profile (flavor and aroma) for certain varietals, such as British or German Noble hops, understanding that at some point things go downhill and become grassy, oxidized and off putting. I suspect the more high-alpha hops will mask some or all of that refinement at least early on.
Not dissing, and will be experimenting myself.