Hi @krisaue -
That’s an interesting idea! In my experience, multiple fathom-x connections in close proximity don’t work - such as trying to use two twisted pairs in a tether to carry two fathom-x connections. That said, I’ve never tried the extension approach you describe - only one way to find out for sure!
Typically performance of the existing hardware is limited to 300m for the standard, and 200m for the slim tether. Newer versions of the module used can support longer lengths!