What happens if you use auto-fire during Ocelot's interrogation?

Before he begins Solid Snake's interrogation, Ocelot says:

"Don't even think about using auto-fire, or I'll know."

If you use auto-fire anyway, what happens?

Solution 1:

If the game detects that you are using autofire, the electrocution continues, controller input is disabled and you'll die.

The game detects autofire via a button-press threshold. If you get over this, the game assumes you use autofire and you'll die.

Reading over some sources, it appears that some auto-fire controllers simply won't work (the auto fire is disabled) and some controllers won't be detected (because they don't reach the button-press threshold).

Sources:

Metal Gear wikia

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