Might be true if I was stopped down, but I would be using it in a situation where it would be wide open at f2.8, not much DOF there.
I have a day shot taken with the D3000 that has detail from the bat hitting the ball to the foul line some 330' away. (70-300 probably around f8 and ISO 400)
BTW the macro DOES focus at other than 1:1 distances, it reaches out all the way to infinity. How about that!