  We apply the color-magnitude intercept calibration method (CMAGIC) to the
Nearby Supernova Factory SNe Ia spectrophotometric dataset. The currently
existing CMAGIC parameters are the slope and intercept of a straight line fit
to the first linear region in the color-magnitude diagram, which occurs over a
span of approximately 30 days after maximum brightness. We define a new
parameter, $\omega_{XY}$, the size of the ``bump'' feature near maximum
brightness for arbitrary filters $X$ and $Y$. We find a significant correlation
between the slope of the first linear region, $\beta_{XY, 1}$, in the CMAGIC
diagram and $\omega_{XY}$. These results may be used to our advantage, as they
are less affected by extinction than parameters defined as a function of time.
Additionally, $\omega_{XY}$ is computed independently of templates. We find
that current empirical templates are successful at reproducing the features
described in this work, particularly SALT3, which correctly exhibits the
negative correlation between slope and bump size seen in our data. In 1-D
simulations, we show that the correlation between the size of the bump feature
and $\beta_{XY, 1}$ can be understood as a result of chemical mixing due to
large-scale Rayleigh-Taylor instabilities.
