Servo setup instructions inconsistent

[scruss]

In Setting Up the Motors - Pen Servo Setup - Test the Motion, it says:

… Not all servos travel the same way. If yours is going the wrong way, send $3=4 to reverse the Z direction.

According to $Stepper/StepInvert or $2 – Step port invert, mask, that would invert Z but revert Y. With the default for the midTbot_esp32 being $3=2, wouldn't setting $3=6 (invert both Y and Z) be required?