reb, a couple of thoughts.
"Recency bias" is pejorative, but I'm a cautious supporter! Especially for young pitchers whose capacities are changing. If a guy has learned new skills, it makes best sense to evaluate him as he is now, with those skills, rather than evaluate him as the pre-skill guy. Horton got faster; his command got better; he developed the slider. He flashed pitches in June that trackman captured, that were not there in March.
"Recency bias" is more appropriate for young pitchers than for hitters or vets. Young pitchers really do learn new grips and new pitches that make them better, sustainably so. And show up with sustainably increased velocity. Their skills and capacities can change significantly. Hitters can't "learn to hit" the way a pitcher can "learn a new grip", so "adding a skill" isn't really a thing for hitters.
The small-sample is a legit hesitation and risk for sure; who knows how sustainable any of it will be? Horton didn't pitch until March 29, or start until April 14. His postseason (31IP) was barely smaller than the regular season 53IP.
I trust the thoroughness and logic of the Cubs analysis, and accept the associated risk. I'm sure they are well aware that there is no safety in either Horton or Ferris. You can have great process and logic and infrastructure and philosophy, but it comes down to individual players and health.
Twenty year ago I trusted the process and liked drafting Brownlie, Blasko, Luke Hagerty, Justin Jones, and Billy Petrick, too. Seemed like a great, high-ceiling haul that could hypothetically combine with Prior and Kerry Wood to set up a pitching dynasty! Opportunity unfulfilled.