  The relative phasing of the X-ray eclipse ephemeris and optical radial
velocity (RV) curve for the X-ray binary IC10 X-1 suggests the
He[$\lambda$4686] emission-line originates in a shadowed sector of the stellar
wind that avoids ionization by X-rays from the compact object. The line attains
maximum blueshift when the wind is directly toward us at mid X-ray eclipse, as
is also seen in Cygnus X-3. If the RV curve is unrelated to stellar motion,
evidence for a massive black hole evaporates because the mass function of the
binary is unknown. The reported X-ray luminosity, spectrum, slow QPO, and broad
eclipses caused by absorption/scattering in the WR wind are all consistent with
either a low-stellar-mass BH or a NS. For a NS, the centre of mass lies inside
the WR envelope whose motion is then far below the observed 370 km/s RV
amplitude, while the velocity of the compact object is as high as 600 km/s. The
resulting 0.4\% doppler variation of X-ray spectral lines could be confirmed by
missions in development. These arguments also apply to other putative BH
binaries whose RV and eclipse curves are not yet phase-connected. Theories of
BH formation and predicted rates of gravitational wave sources may need
revision.
