Both SC2 Pro's power supplies required if running at low strength?

It turns out my ideal overall strength is a fraction of its full power. Is there a certain threshold where if you’re below it, you don’t even need to have the second power supply connected at all? They’re quite big, so if I don’t need the second one, I’d prefer to not have it installed.

You might run into issues with momentary power consumption exceeding the capabilities of a single PSU even with low torque, as with servo motors the power consumption is not always proportional to torque level. Therefore we recommend to use both.