electricity is always willing to take the easiest way out beez,in other words it takes the path of least resistance.
in the case of the resistance of your body compared to the resistance of the air gap across a spark plug tip,u guessed it,your body has least resistance,so electricity will favour the path thru your body when u present it the option over the spark gap.
if u touch anywhere down line of the coil,u will receive the bulk of the current flow to ground. u also risk frying the coil from overcurrent if the leaks get substantial,ie lower resistance.

"hole-shot" is just another term for launch control.
if u get an additional msd control module to talk to the 6AL,u will be able to set a spark induced rev limit to have a set launch rev limit before u dump the clutch,not exactly useful on a standard auto tranny beez.
the second step of the 2-step is just an overall spark induced motor rev limit,your motor already has a fuel induced one.so unless u want a lower overall rev limit,then also no use to u,unless u change the fuel limit with aftermarket ecu.
some people prefer the popping & banging of a rough spark limiter.