  The Hercules ultra-faint dwarf galaxy (UFD) has long been hypothesized to be
tidally disrupting, yet no conclusive evidence has been found for tidal
disruption owing partly to difficulties in identifying Hercules member stars.
In this work, we present a homogeneous re-analysis of new and existing
observations of Hercules, including the detection of a new potential member
star located $\sim$1 $^{\circ}$ ($\sim1.7$ kpc) west of the center of the
system. In addition to measuring the line-of-sight velocity gradient, we
compare predictions from dynamical models of stream formation to these
observations. We report an updated velocity dispersion measurement based on 28
stars, $1.9^{+0.6}_{-0.6}$ km s$^{\rm -1}$, which is significantly lower than
previous measurements. We find that the line-of-sight velocity gradient is
$1.8^{+1.8}_{-1.8}$ km s$^{\rm -1}$ kpc$^{\rm -1}$ along the major axis of
Hercules, consistent with zero within 1 $\sigma$. Our dynamical models of
stream formation, on the other hand, can reproduce the morphology of the
Hercules UFD, specifically the misalignment between the elongation and the
orbital motion direction. Additionally, these dynamical models indicate that
any radial velocity gradient from tidal disruption would be too small,
$0.00^{+0.97}_{-0.91}$ km s$^{\rm -1}$ kpc$^{\rm -1}$, to be detectable with
current sample sizes. Combined with our analysis of the tidal radius evolution
of the system as a function of its orbital phase, we argue that it is likely
that Hercules is indeed currently undergoing tidal disruption in its extended
stellar halo with a line-of-sight velocity gradient too small to be detected
with current observational datasets.
