3) Everybody rushes in to buy ScV, which causes all the stocks in that slice to become mid-cap growth!
4) Nobody wants mid-cap growth, so it's time to reslice.
5) Now we have a new index with the next generation of ScV. In the meantime, the unloved mid-cap growth are getting cheaper since we took them out of the index.
6) Oh look, all the mid-cap growth got so cheap that they've become ScV again. Reslice, reindex, and repeat forever!
You basically capture the growth of stocks going from small cap to mid cap and from value to growth on a continuous basis. Pretty brilliant, isn't it? Forget the "risk premium" nonsense.