OK, I'll bite. Keep in mind that I'm not a EE, I just play one at work. *grin*
How about if they put the Cat5 in a single, long hose through the ground without any copper connectors, then run a copper wire (very well grounded at each end) on top of it, connected to the upper side of the insulating material? That way, you'd get the best of both worlds - A good connection through a grounded medium and have a solid ground to carry any strikes away. Might be expensive, but doable. Duct take can work magic, you know!
That being said.. Each of you picking up a decent 802.11B and running them in bridge mode wouldn't really be all that expensive and would certainly be a lot easier and probably safer.
Last point. A lot of people measure the distance between two locations and decide it's within reach. What they don't factor in is that the cable run inside the premise ALWAYS seems to be longer than you think it is. Of course, I've seen Cat5 runs operating at 450 feet without much problem, AT 10BASET speeds - Push 'em to 100BaseT and, Houston, we've got a problem.
- G