Excessive splitters usually is a sign of ancient cabling as well. I know for a fact that Comcast has passive gain amps specifically built for dealing with homes

Excessive splitters usually is a sign of ancient cabling as well. I know for a fact that Comcast has passive gain amps specifically built for dealing with homes that have more than like 8 tv's and a modem. You (or your dad, it's unclear) probably were hooked up a long time ago, or the tech didn't know what he was doing.