Have you considered or attempted to make the pipe to ground toggleable like with the regular/underground pipes? So the original functionality of undergrounds can be retained alongside what this does. For example, normally, underground pipes can cross each other without issue, but that functionality is lost with this.

No, this is intended. You both gain and lose flexibility with this system, so your designs have to work around the changes.

Yeah, I'm noticing the intricacies more the more I get into it. Advanced Oil Processing is interesting. I'm starting to appreciate the long undergrounds and corners without having to go above ground more than the crossing convenience.

Enjoy!