Obama and Arnold naturalized in the same year, 1983.
The State Department has updated the Foreign Affairs Manual again:
7 FAM 1292 Loss of Nationality and Minors i. (3) (CT:CON-361; 03-01-2011)
Interviewing a minor: When conducting the initial interview with a minor and during the renunciation procedure, you should have at least one other person present. The parents and guardians should not be present. As noted, the interview should take place in the presence of the consular officer and a witness, preferably another consular officer, another Foreign Service officer (nonconsular) or locally employed staff (LE staff). You should alswo explain that upon reaching the age of 18, the minor has a six-month opportunity to reclaim U.S. nationality. See FAM Exhibit 1291, A Sample Letter to Accompany CLN for Minor Renunciants, which should be provided to minor renunciants together with an approved CLN;