That's what I was thinking, don't really know what's behind that. Maybe, looking at Lorang, the whole thinking at Bora is very much about training and VO2, not so much about racing instinct and technique? WKA will probably know more about this.
Yeah, there have been a few interviews with Lorang and also Denk which help explain this signings. Generally, your totally right about it being a lot about exceptional numbers. I think Roglic, Woods etc. have shown cycling coaches and teams that a big engine and a lot of good work and coaching make it possible for athletes from outside of cycling to enter the sport and be (very) competetive in a few years time.
That being said, Lorang obviously has his triathlon background as a coach. So he knows how to coach and handle not only cycling but also other disciplines. He knows what engines good runners possess, how that might translate to cycling etc. And he has obviously not only been "a" trainer in triathlon but he coached Frodeno and Haug to Hawaii titles.
Lorang has also stated that Bora has been looking outside of traditional (road) cycling for some time now in order to find talent. He is pretty connected in the coaching world outside of cycling, Bora as a team have worked with experts from other disciplines (mainly winter sports like Biathlon) and since Lorang has become Head of Performance he has a lot of say within Bora. Denk trusts him. Lorang developed Buchmann, Ackermann, Bennett into world class athletes. All have been given time to develop, they were cautious and had a long term plan, which is exactly what you need if you want to transform guys like Zwiehoff or Palzer.
This openness towards newly converted cyclists can also been seen as an investment into the future. There are a lot of young talents every year who don't make it in their respective sport and are looking for something else. There are athletes who want to switch to another sport because they like it more than what they have been doing etc. Just look at Tirols Florian Lipowitz. He is a Biathlon convert who has just been riding his first year professionaly. Has outstanding power numbers, amazing results in some Gran Fondos at a young age and liked cycling, which he did as 2nd discipline, so much that his father went up to Lorang and talked with him, which led to testing and a contract at Tirol. And a possible future at Bora. What I'm saying is, it opens up possibilites to acquire great talent. Especially if they view your team to be open about this stuff and having already developed such athletes.
And then there is also the commercial value. It's always a great story. Journos love it, commentaters love it and sponsors therefore as well.
In the end, they will test these guys extensively, and know them pretty well. With Zwiehoff for example Bora weren't the only team who were in on him. He shattered some performance test records at Jumbo Vismas test center. When they were made aware of his results, Lorang and Bora reacted and invited him.
The things they have to teach them is technicals and tactical skills, riding in a buch etc. Marlen Reusser is a great example in the womens peloton of a rider who has transitioned late to professional cycling , has outstanding power but lacks technical skills. Thus crashing often and other riders pointing that out and trying to avoid riding alongside her in the bunch. Someone from MTB like Zweihoff will probably adapt rather soon, with Palzer I don't know how his technical abilities from running and skiing will adapt on the road. But Denk certainly isn't the guy to start a project like this if he and the team weren't convinced that there is a pretty good chance of it being succesful.