When our house was rewired, the sparky ran a combined phone and fibre cable from the office to the house outside wall where the copper phone line pops out of the ground conduit. He said the rules are you should leave some amount of cable say 1.5m coming out of the house, so this is coiled up then connected to the phone line. I am under wife pressure to tidy this up by putting it in a box rather than leaving this coil lying around. What is the smallest radius I can bend both copper twisted pair and fibre cable, without affecting its performance?

Also, I'll need to cut and rejoin the phone cables. Are insulation displacement connector like these good enough for this purpose?

https://www.jaycar.co.nz/crimp-wire-connectors-2-3-wire-pk-8/p/HP1214

Thanks