Gautham's reasons for Vijay dropping Yohan 

Gautham revealed to a recent interview to DC that the movie announcement was made after he had given a one-liner to Vijay which he liked last year. When Gautham narrated the final script recently, Vijay felt that he was not cut for the particular story. Since Gautham didn't have time to re-write a new script, Vijay had requested if he could move on to director AL Vijay's project. This resulted in Gautham opting out of this project. There was no mud-slinging nor bad-mouthing on this topic from both parties, which gives us hope that Vijay and Gautham could come together when the timing is right.

Source close to the matter revealed that this incident happened more than a month ago and mentioned that Vijay who has been giving a lot of importance to the script of-late did not feel that Gautham was really ready. It was reported that almost all the characters in the movie were non-Tamil actors with a lot of English dialogues including a number of action sequences shot in foreign locations. After the debacle of a recent movie that relied on action sequences, Vijay apparently felt that Yohan may be too alien for Tamil audience. Hence the reason for Vijay opting out of Yohan.

Additional reason quoted is that Gautham's announcement of Suriya's project Thuppariyum Anand was not received well by Vijay. Vijay saw the media shifting the focus to Suriya and Gautham. Vijay was concerned that between all the ongoing commitments of Gautham and Thuppariyum Anand, Yohan may get squeezed and compromised. 

With Gautham having one less project to worry about, this may be the perfect opportunity for the director to get his bearings back again.

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