Why is one year a better answer than four months? Why not two years or five years? Is four months not an adequate time to accomplish the strength goals they set for him? And how would we possibly know that?
It's a two-part answer:
Part 1: Does it work and how much time is needed.
The NCAA plays 2 games per week. The rest of the week is for college, practices, weight training, and rest. Minnesota Gophers play 36 regular season games, which would equate to 18 weeks. That's about four months. It doesn't include any conference championship games or the NCAA tournament, if they qualify.
Part of the draw of going to the NCAA route is due to the weight training aspect. They have metrics that are tracked as proof of success.
With that knowledge, someone can create a specialized program for Carlsson as well as Luneau. They can also track the metrics of improvement from when they started if the individual has met the intended goal. Since the specialized program is probably individualized, the end goal may differ. The original thought for Carlsson was two months. After revisiting the progress, they're extending the process, but also also adding more games per week. The process may not be as intensive in this extension period.
Part 2: Why is this odd duration?
Verbeek wants Carlsson to gain NHL experience while weight training. It's apparent that Carlsson isn't a ripe prospect. The NHL exposure does give Verbeek insight on what he has in the prospect, which is valuable knowledge. If Carlsson stayed in the SHL, then the org would have to wait a year to see how well Carlsson's game can translate to the NHL level. Verbeek isn't stuck in the dark now with Carlsson in the NHL this season.
Since Verbeek made a commitment to Carlsson staying in the NHL all season, then Carlsson is now on an NHL schedule than an SHL. Carlsson can continue the weight training after the season, but already have NHL experience. This should give Carlsson a big jump in production between his rookie season and next. The big jump in production happened to Z and it's happening with Mac this year.