PFC is the designation for Private First Class . One stripe with pointy part up (chevron for the Brits) as designator on sleeves.
Those entering the service as enlisted men/women are all Privates. No insignia of rank.
Therefore, it may be deduced that Wintegreen was once a PFC and had his rank reduced as a disiplinary measure. Private is low man on the totem pole!
Reduction in rank for infractions of the UCMJ (Uniform Code of Military Justice) is "to encourage the others."
although it sounds much classier in French. "Pour encorage les autres" if spelling wrong, please correct.
wow