Filibusterers have never had to read the phone book. Strom Thurmond’s recitation of recipes and phone books was pure theater, tolerated only out of Senatorial courtesy: the majority had already secured the votes for a quorum.
To mount a filibuster, one Senator need only sit aside and simply say, “I suggest the absence of a quorum.” He can do that again and again and again. This was proven by Alan Simpson of Wyoming when he blocked campaign finance reform in 1988. The rest of his supporters can go home.
Cite: The Myth Of The Filibuster: Dems Can’t Make Republicans Talk All Night.