Maybe it would help if I explain:
I currently have an issue. That issue is that there are few server chassis that can support watercooling. Why must I watercool? Among other things, so that I don't have several sets of fans reving at all hours. Now I could throw down $1.7k to have a chassis like Linus, but since I need more than one, that seems impractical... So, whilst looking at parts I came across PCI Slot passthroughs for tubing, and thus the idea to have an external watercooling setup took shape. No longer would I need to pass up the smaller 2u and 3u chassis since I could watercool them if needed.
I was planning on suggesting such a project for an episode, having them watercool all their servers to one Extreme Rad.... But doubt it is something for them to try.