I do not fully understand. I upload all kinds of stuff all the time for future use. Usually audio files. It does not come in as known unless I already know it. I’m sure no one cares about this.
There is truth to the Challenges however. They could cause you to do things you would not normally do. I myself in the one challenge listened, mostly in background, a lot on the days when it was encouraged. That is what Steve seems to recommend and it did feel like it improved my listen skills even if only for their stories.
The linking was also extreme but helpful. I went to some of my uploaded materials, went to the vocabulary list and if I knew marked known, if I did not I linked it and put a definition. It was beneficial as now as I work thru the materials, I do not have to deal with the blue words as I already did. I would have done the exact same activity, which I learned from watching Steve, but usually one at a time.
I usually do not give a rat about the challenges, but this particular one was a team and my lack of progress was harming the team. That I will avoid in the future as it made me divert my regular activites. But it was beneficial.