Re: A rational and reasonable write-up of the issue.
[ For avoidance of doubt, I am the primary author of Fuse ]
"Though on the point about the FUSE emulator, I don't see why notifying (or not) the originators of an open source product that you want to use it is relevant, so long as the terms are complied with."
Correct. This was an attempt to explain to people who might not necessarily understand the difference between free as in beer and free as in speech software that RCL did nothing legally wrong by not talking to the Fuse team before using Fuse in the Vega+. It didn't entirely work, but I think it helped.