When Gary Burghoff decided to leave the series, Mike Farrell tried unsuccessfully to talk him out of it. Specifically, Farrell cited the lackluster, relatively unsuccessful TV careers both McLean Stevenson and Larry Linville had once they left the show and ultimately he was right. Burghoff's subsequent television career never took off.
Gary Burghoff was having marital problems at the time of filming, soon to end in divorce. In the scene where he bonds with a nurse at the airport, but then must leave her to return to the 4077th was so hard on him, he burst into tears after filming.
There are characters named LaGrow, Hough, Forster, and Reuss. At the time, Lerrin LaGrow, Charlie Hough, Terry Forster, and Jerry Reuss were all pitchers for the Los Angeles Dodgers.
Burghoff's decision to leave the show had come after an extended leave from the series. In Season 6, he did not appear in several episodes, which was attributed to burnout, though it's also been speculated that it was more to do with the fact that he was generally disliked by his castmates and was often difficult to work with.