@fungi4 I thought I would just answer this so Karthik doesn’t have to answer it. This is legal as long as your wires are not at risk of entanglement (pretty easy to do, look at videa example). Here is an example:
Come on guys, try to at least use the forums while you’re on them. 
Just so there isn’t any misinformation. You don’t need to have a rigid connection like in the video shown.
Karthik answered this in here: https://vexforum.com/t/answered-tethers-on-the-divided-field/35363/1
Ok, I was just using that as a good example
It’s already been done in skyrise, with one robot building the pylon and the other scoring cubes.
How are you planing on using a dual bot? I can see a big expanding wall, but a dual bot for returning stars would also be pretty neat.