Could you clarify the rules about using string on VEX IQ competition robots?

The VEX IQ Curriculum on the website includes using string for the pulley projects. Some of our sets came with rolls of VEX string, although those may be our PLTW sets. I understand that it is legal to essentially “make” string by tying rubber bands together, but is string allowed (and what thickness, strength and so forth) on the competition robots? thanks.

There are no specific allowances for the use string. However you are allowed to use any string or string like items that you may find in any of the official VEX IQ or VEX Robotics by Hexbug kits, provided no other rules are violated in the process.