It is funny how you pretend to understand Sc2 as an eSport and know about Nani. He even said in the interview that at the end of the day, they are just excuses and do not justify his results.
About his public speech, let us send you over to Sweden, get interviewed in Swedish and see how well you speak. Nani has said many times in the past that results are what matters and everything else is extra. Why would a team-less, nonsalaried player who cares very little with public opinion, need to learn how to publicly speak?
You say that he should tell his group, what are you talking about? There is no group for him. You say he should get a schedule to practice constantly, how? He went to Dallas (2nd to 4th of Nov) to Dreamhack (22nd to 24th of Nov) to IPL (29th Nov to 2nd Dec). Assuming everything was air tight, and there was only one day to arrival and one day back home, he had a total of 19 days to practice between Dallas to IPL. In 19 days, do you realize how far the metagame goes? Do you realize how even one little fixing in a strategy takes? Let alone to learn new ones? Or how rigorous basic 8+ hour training is, just to keep up mechanically? Obviously not.
Nani does constantly practice WHEN HE CAN, otherwise he wouldn't be producing the results that he is.