A consistent criticism A.R. Rahman has had to face, including from fans and friends who mean well, is that he is more of a sound engineer than a music composer.
In other words, he is good at dicing and slicing various sounds and tracks, and piecing them together at god forsaken hours in the privacy of his Madras studio, unlike the old maestros, like Ilayaraja, who did it all in one go. Which is why it was difficult to reproduce the same sounds in live concerts and orchestras.
A live concert in Dubai in the early 2000s proved otherwise, as this Rajnikanth number sung with magisterial command by S.P. Balasubrahmanyam shows.