I don't know how to do it myself, but I am aware that this VIP tutorial goes through the process of animating a plane and missile, where the missile hits the plane and it explodes (see the AVI file linked in the tutorial desc).
I think he means along the lines of Edit Polygons -> Subdivide.
If you use Polygons -> Smooth, it will subdivide the polygon but shift vertices around to form whatever curve your selected faces were naturally forming. Ex: Smoothing a box will form a shape resembling a sphere... not just a box with a lot more polygons per side.
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