I feel that coaching can only do so much for a player, natural gift is an essential component
This ofcourse is bad news for many players but what I am saying here is that batting coaches are probably a luxury and not a necessity
I feel this does not take into account Smiths entire career. I will not speak about Miandad because he came up through the streets, in an era of limiting coaching within Pakistan, both domestically and within the international set up.
Now, back to Smith - I agree that natural gifts are important for all athletes, or anyone that achieves greatly in any field. Smith's greatest gift may be his hand eye coordination, however this is where the nurture v nature dynamic comes into play: baby Smith may have been born with this gift but all those years of practice playing in the back garden, then playing at club level, junior, state etc will have groomed this natural gift, which many other children will have also possessed.
Having said that, if we think back to Smith the debutant, he was a leg spinner who was a clumsy fielder, the gift of hand and eye we now see did not seem apparent. How dd it improve so much? How did he go from leggy to lower order slogger to bit parter to terrific batsman? He clearly wasn't born or naturally gifted as a batsman. He still isn't in the same way Kohli, Williamson, Babar seem to be. This clearly means he was coached, put in tonnes of hard work and coached some more. Listen to some of Smith's interviews about his transition period, he speaks glowingly about the coaches he needed to get to where he is today.
Nature v nurture is more like nature AND nurture.