Whatever your thoughts on Hughes and consistent with what I have posted on other threads, this will be his third and FINAL shot at Test Cricket - there is never a fourth.
He has made some technical changes with his foot movement, but you can't expect it to be down pat overnight. There are still a few ugly dismissals nicking to slip. He was ok in County cricket this year but a bloke called Chris Rogers did better. As his coaching guru put it "either he's improved or the domestic bowlers are shit". The answer is it could be a bit of both.
Is he ready? He thinks he is, but up until the cold harsh realities of his technical flaws were explained to him, he didn't think he had a problem then either.
Whatever your thoughts this it - fail and he's finished for all time.
Sri Lanka is hardly going to be a testing environment for him.