  The recent determination of the charged $\pi NN$ coupling constant,
$g_{\pi^\pm}$, by the Uppsala Neutron Research Group implies that there may be
considerable charge-splitting of the pion coupling constant. We investigate the
consequences of this for the charge-independence breaking (CIB) of the $^1S_0$
scattering length, $\Delta a_{CIB}$. We find that $\Delta a_{CIB}$ depends
sensitively on the difference between $g_{\pi^\pm}$ and the neutral $\pi NN$
coupling constant, $g_{\pi^0}$. Moreover, if $g^2_{\pi^\pm}$ is only about 3%
larger than $g^2_{\pi^0}$, then the established theoretical explanation of
$\Delta a_{CIB}$ (in terms of pion mass splitting) is completely wiped out.
