I think there's two different but similar ideas. When you view the Tablo "remotely" there is a bitrate transcode that might happen (occupies a free tuner) based on your "remote" streaming quality setting.
So, there's the idea of "Live TV" recording to file setting (Tablo is always recording to file), the idea of scheduled recording max quality and there's also the "remote" streaming/viewing quality (which occupies a tuner to do).
The latter has more to do with "sending" if you will. But does occupy a tuner and normally only applies to remote viewing.
Not an answer, just dropping off some more info for consideration (by everyone).