In the review you say: “… and the 100% use of rye might have something to do with this all.”
You may want to review the tweets by Davin. He said: “@The_Casks Not sure what you are asking. Lot 40 90% rye grain 10% malted rye. AP Dark Horse 40% 6yo pot rye 51% 12yo column rye.”
He also said “@The_Casks #DavinTT Lot 40 – 100%; Dark Horse 92 or 93%”
So, Dark Horse contains ~92% rye. The rest is a combination of Straight Bourbon (from Beam) and ~1% sherry.