This section is dedicated to discussion of DTA engine control units such as the DTA E48 EXP, P8 Pro, DTA S40, S60, S80, and S100, as well as all things ECU related.
ANA1 MINIMUM / MAXIMUM AGGRESSION / USE ANA1 TO SET AGGRESSION
When using a potentiometer connected to the ANA1 input to allow a dashboard settable “Aggression” for the traction control these numbers set the allowable range of settings. Because the switch on an S60 is not available to turn traction on and off, this knob allows the traction control to be turned off. A voltage above 4850mV presented to the ANA1 input turns off the traction control system.
So yep, I think you're right. I had always read that quoted above from the manual as it wasn't possible.