Based on our team's experience, it's also a good idea to have a short sacrificial cable off the tether port that is not screwed down. Our rookie season, we had a robot runaway on tether, and nearly ripped the tether port off the RC when the OI carriers failed to keep up.
This year, we used a short bit of ribbon cable with serial connectors on both ends, and ty-wrapped the ribbon cable down to the electronics board on the robot to make sure the cable would take the strain, rather than the RC, if we had a similar problem. (We also improved our programming to reduce the likelihood of the robot going rogue on us
)