  The Comisso-Asenjo mechanism is a novel mechanism proposed recently to
extract energy from black holes through magnetic reconnection of the
surrounding charged plasma, in which the magnetic field plays a crucial role.
In this work, we revisit this process by taking into account the backreaction
of the magnetic field on the black hole's geometry. We employ the Kerr-Melvin
metric to describe the local near-horizon geometry of the magnetized black
hole. By analyzing the circular orbits in the equatorial plane, energy
extraction conditions, power and efficiency of the energy extraction, we found
that while a stronger magnetic field can enhance plasma magnetization and aid
energy extraction, its backreaction on the spacetime may hinder the process,
with a larger magnetic field posing a greater obstacle. Balancing these
effects, an optimal moderate magnetic field strength is found to be most
conducive to energy extraction. Moreover, there is a maximum limit to the
magnetic field strength associated with the black hole's spin, beyond which
circular orbits in the equatorial plane are prohibited, thereby impeding energy
extraction in the current scenario.
