  We present two-dimensional kinetic simulations, with a broad range of initial
guide fields, that isolate the role of parallel electric fields ($E_\parallel$)
in energetic electron production during collisionless magnetic reconnection. In
the strong guide field regime, $E_\parallel$ drives essentially all of the
electron energy gain, yet fails to generate an energetic component. We suggest
that this is due to the weak energy scaling of particle acceleration from
$E_\parallel$ compared to that of a Fermi-type mechanism responsible for
energetic electron production in the weak guide-field regime. This result has
important implications for energetic electron production in astrophysical
systems and reconnection-driven dissipation in turbulence.
