[Ignitionnet]

So long as the modem is good enough and fully compliant to standards no reason why it can't deal with the power levels I mentioned.

High power levels can cause issues with modems, not so much from the power of the cable modem signal but the overall power of the RF hitting the modem's receiver causing distortion by overdriving it.

Not so much the cable modem signal but the other few hundred MHz of RF hitting the modem receiver and how well it isolates channels it's not tuning.