Most CT's are shipped from the factory new with shorting bars installed across its terminals for safety. It is the meterman's responsibility to realign these, which is usually done by loosening a clamping nut, turning the shorting bar sideways, (where it doesn't touch either terminal) and re-tightening the clamping nut so it doesn't move.
If the bar was still there, you could have reversed the above procedure and left the CT's shorted directly at the CT. Then you would have been free to remove the old wire and use the terminal strip.
In the long run, this probably would have been safer anyway, since the CT would be shorted regardless of what was done externally. I'm surprised the POCO abandoned it.
