Not cheating at all! It should be happening more IMO!
First, there’s a lot of parallel chatter and interests kept separate because people are on different platforms.
Second, bringing down the boundaries between instances and platforms (so that don’t all have to use screenshots all the time) is what the fediverse is about)
Third, using existing communities and platforms to activate new communities and platforms is supposed to a super power of the fediverse, as it makes it easier and easier to kickstart new things as the fediverse grows
Fourth, and getting back to the second above, the fediverse’s “killer app”, IMO, is the eventual creation of a diversity of communities and platforms that interoperate in a useful, flexible and engaging way for the user.
At the moment, I’m actually frustrated at the lack of cross platform engagement between lemmy/kbin and mastodon. A big part of it, IMO, is the simplicity of mastodon’s UI and how integrating with any other platform with a more sophisticated UI becomes difficult. Right now, for instance, mastodon has no nice way to deal with a community/magazine or a post with multiple threads of comments beneath it, as all mastodon does is see everything as a flattened stream of posts in reverse chronological order.
Right now, posting from mastodon to a community is the only way to bring these worlds together that works for users of both platforms, except for the user making the post, which is a problem.