I found a truck roll of verizon fibre half way up the tree. yakasuma-something-japanize optical cable. Has a hard black shell and about 2/3" inside. I didn't take the end cap off, got enough scsi as it is. What you saw was probably verizon laying conduit and comcast waiting for the ditchwich to knock out the television service. They have to share since public utilities don't like when you dig up their lines for them. That conduit is there because if you back hoe fibre they get to do it all over again.