Looks like no one has an answer to the serious questions posed in #119.
The biggest question to ask is why would Sierra Nevada want to do this in the first place? Can they not make the beer they want to, without outside help?
And why did they discontinue working with the Germans?
Or maybe, just maybe...the Germans simply said "Nicht mehr".
Would Anheuser-Busch partner with Molson-Coors to produce a seasonal beer?
Would General Motors partner with Ford Motor Company to produce a new sports car?
The SN folks have been going to Germany for years. Hop selection and equipment sourcing trips, for example. Then there is Drinktek (SP). Brewers start friendships. Sierra Nevada is known to be excellent in quality and technichnology. I bumped into the brewer at Mahrs in Bamberg, and he was really excited to have been selected that year, had his Sierra Nevada baseball cap on.
Some of the collaboration brews used malts sourced with the breweries, Steffi for example. There was an older hop used one year, and when they worked with Bitburg the used the Bitburg yeast and hop blend.
Why did they stop? My take is that there were too many other things to take care of. The selection would have happened before Covid hit. The Germans saying no? Turn down the trip to the release event in the USA? I don't think so.
Car companies do work on joint projects fairly often, but not image cars like a sports car. GM and Ford have done joint development on a couple of transmissions (a huge investment), for example. I remember joint projects for different delivery vans.