When Janelle and Frank are eating out at an Asian restaurant their bowls of dragon rice continually fluctuate from full to half to full again.
While Mo Dean watches a Sesame Street sketch with Robert MacNeil mocking Jeb Magruder's testimony in the Watergate Hearings, John Dean worries whether he will be similarly made into a laughingstock and portrayed as Beaker. However, the Muppet character, Beaker, made his debut in episode 202 of The Muppet Show (1976) that first went to air in 1978.
During his testimony prep for the Watergate hearings (1973) , John Dean is worried about being compared to the Muppet Beaker. Beaker did not debut until the second season of The Muppet Show (1977).
John Mitchell and a senator are putting golf balls at a country club somewhere. The grass on the green is so long that the balls actually bounce rather than smoothly roll. This would not be the case at even a public course, much less a club where powerful individuals play.
At home after his testimony, John Dean makes a Gin & Tonic and offers to make Mo one, then remembering she is pregnant, apologizes and offers tea instead. In 1973 the science on alcohol and pregnancy was brand new and it was not widely known until the 1980s. What is something of an obsession now was not even a consideration at that time.
Frank makes reference to growing up in North Augusta and eventually returns there to live with his mother. The script (and a road sign) indicates he's going to Georgia, but North Augusta is in South Carolina.