Deepika did train at Anupam Kher's acting school before OSO.
SRK trained with a renowned theatre guru (I forgot his name atm).
Trappings of commercial stardom probably took actor outta them.
Mithun for eg also went to acting school. But later got into masala films and one cannot believe he was trained actor or won national award for his first film Mrigaya and did many acclaimed films.
Shatrughan Sinha is from FTII but he got sucked into commercial films and began to believe in myth of his own style, mannerisms, which became caricature later.
Depends on how actors use their training. Not everyone remains natural like say, Irrfan, Manoj Bajpai, Ashutosh Rana, Jaya Bachchan, Shabana, Pankaj Kapur, Rajkumar Rao, Mita Vashisht, Surekha Sikri, Om Puri, Naseer etc even after film school training.
Kumkum Bhagya
Anupamaa
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