This'll add some more fuel to this fire -

There are three differences between car and airplane electrical systems
that apply here -

1) Only aircraft have a master switch relay - which may stutter if the
battery is low, and
2) Only aircraft have an alternator stator circuit breaker that if
tripped causes the alternator to disconnect abruptly.
3) Aircraft also have a circuit breaker and switch on the alternator
rotor.

Given number 1, if the avionics are on, the starter could briefly still
be connected to the avionics with no battery in the circuit allowing
the starter collapsing magnetic field to put a helluva positive voltage
spike into the avionics stack. That's why everyone is supposed to turn
off all electronics before engaging the starter.

Cessnas have a starter circuit activated drop out avionics relay, but
the avionics relay mechanical timing just might still allow the spike
to get to the avionics. Only if the battery stays in the circuit, does
the collapsing starter field pulse stay confined to arcing the starter
contactor.

Remember that there are no faster fuses than silicon cuircuits. I
would guess most 14 V electronic stuff could withstand say 20 V, but
certainly not 100 V

Number 2) causes the current in the alternator stator to collapse
putting a major (negative I think....) voltage spike into the
alternator regulator. If the regulator is solid state, it could be
wrecked. If it is mechanical, it could probably withstand this.

I don't think Number 3) presents a theoetical problem to the system.

You don't get voltage transients when connecting up inductors. You get
them in spades when you quickly interrupt the current flow to them.

I'll bet Jim Weir has some thoughts on this.