As in what’s in use with CAT5, etc. I know they started using balanced back in the day of telegraphs to reduce cross-talk. Ball Labs probably starte dthe practice of twisting for reducing cross-talk even more as the requirement and bundle count increased. But, someone came up with using variable twist rates so you reduce the cross-talk even further.
Who/when? I find info on variable rate twist but nothing on the who/when.