"Star chamber" is a fabulous term that would seem to describe the situation quite well. Thanks, added to my internal dictionary!
GotUserList (Ok userList) -> ...
and another that looks like: GotUserList (Err _) -> ...
Since we need to pattern match on both types of the Result structure in our update cycle, there isn't really an opportunity to implicitly gloss over a failure to parse. Of course you can try to make the decoder super permissive, but this is harder than doing it the right way. If you're REALLY lazy, you can throw in "Debug.crash" in the failure case, but there's no general solution for throwing grenades at your foot :D