This system also takes into account instances when one has more than one wife. Over a period of time name of the benefactor is also included as Gotra,as a mark of Respect.
He recites the names of Brahmin Rishis as his ancestors in His Pravara?
Lord Rama's Gotra/Pravara is this.
Yajur vEDa Saakhaa adhyaayinE, VaasishTa, MaitraavruNa KouNDinya trayaarishEya Prvaraanvita, VasishTa....Note how meticulously he uses the term Varma , indicating that He is a Kshatriya.
Brahmins must use the term Sarma, Kshatriyas Varma and Vaisyas Gupta after their Names in Pravara.