In the Television Show Dallas, The Repetition of Motives in the Show's Theme Song Matches the Repetition of Letters in the Show's Title

For years, I've found it odd that the second phrase of Jerrold Immel's iconic two-phrase main theme for the popular TV drama Dallas (1978–1991) started exactly like how the first phrase ended. Phrases typically don't do this.

Then yesterday I thought of one possible reason: