So?
Are you suggesting that electricity was required to use the telephone?
“Richard” can’t figure out a “purpose” for cutting the power, therefore nobody cut the power.
Iacoletti,
Can you figure out a purpose for the TSBD's power's being cut off for a few seconds just before, during or after the assassination, if indeed it was cut off?
Maybe to prevent the elevators from working?
The interruption, by virtual hero Jack Dougherty, of a top-secret secret "SHOOT, DAMMIT" radio transmission?
Anything else?
-- MWT

PS Did Geneva's electrified "Steely Dan" cause a short?