comcast "agreement"

Comcast is the only provider of faster-than-dial-up internet in my area (that's right, no DSL). As such, they have a monopoly, and anyone who wants (or needs) to use the internet at modeRn speeds must do it through them. They just mailed a change in the "Comcast Agreement for Residential Services" along with the most recent bill. It contains this passage:

You understand that your computer or other devices may need to be opened, updated, accessed or used either by you or by us or our agents, in connection with the installation, updating or repair of HSI or video services. The opening, accessing or use of your computer, other devices used in connection with your computer, or your video devices may void warranties provided by the computer or other device manufacturer or other parties relating to the computer's or device's hardware or software. Neither comcast nor any its affiliates, suppliers, or agents, shall have any liability whatsoever as a result of the voiding of any such warranties.

Is it irrational for me to be disturbed by this?