That's a good question. I finally ended up putting all my LE units within 2' of each other to run 8 pipes of a bellagio fountain. I used "DMX In" and "DMX Out 1". Removed the terminator on all but the last one. So far this works like a charm and it's rock solid. Let's hope it continues and I did it correctly.
The splitter is a nice feature so I'm interested in the answer to your question.