  Previous analytic and numerical calculations suggest that, at each instant,
the emission from a precessing black hole binary closely resembles the emission
from a nonprecessing analog. In this paper we quantitatively explore the
validity and limitations of that correspondence, extracting the radiation from
a large collection of roughly two hundred generic black hole binary merger
simulations both in the simulation frame and in a corotating frame that tracks
precession. To a first approximation, the corotating-frame waveforms resemble
nonprecessing analogs, based on similarity over a band-limited frequency
interval defined using a fiducial detector (here, advanced LIGO) and the
source's total mass $M$. By restricting attention to masses $M\in 100, 1000
M_\odot$, we insure our comparisons are sensitive only to our simulated
late-time inspiral, merger, and ringdown signals. In this mass region, every
one of our precessing simulations can be fit by some physically similar member
of the \texttt{IMRPhenomB} phenomenological waveform family to better than 95%;
most fit significantly better. The best-fit parameters at low and high mass
correspond to natural physical limits: the pre-merger orbit and post-merger
perturbed black hole. Our results suggest that physically-motivated synthetic
signals can be derived by viewing radiation from suitable nonprecessing
binaries in a suitable nonintertial reference frame. While a good first
approximation, precessing systems have degrees of freedom (i.e., the transverse
spins) which a nonprecessing simulation cannot reproduce. We quantify the
extent to which these missing degrees of freedom limit the utility of synthetic
precessing signals for detection and parameter estimation.
