Currently, the only FVC legal way to keep pwm extension cables together is to zip tie the each side of the connector to some part of the robot. Even splitting the pwm cable to slip a zip tie through, is modifying an electrical component which is not allowed under the FVC rules. Also, custom built or custom length pwm cables is NOT legal for FVC.
I have asked IFI to create a FVC legal product which would function similar to one I found, and use for FRC, made by Maxx Products - a Universal Security Clip. It is being considered and, hopefully, it will be available for next year. If you think its a good idea, you might want to drop IFI or the GDC a post asking to make these FVC legal.
If you'd like to try these clips for FRC here's the link:
http://www.maxxprod.com/mpi/mpi-3.html
Look about half way down the page for the Universal Security Clip.
