Thing is, you are still using a WAS - it is just mounted in a more convenient spot. You are measuring the angle of the steering wheels. This works fine for a system that does not have any slack in the entire chain from the steering wheel to the wheels at the kingpin.
Now a true WAS-less system does not use an encoder, or steer angle sensor. It uses an IMU to measure angular velocity and angular acceleration to steer the vehicle. The set point angular acceleration AOG already is computed. AOG has done that since v3 where it was used to limit steer angle based on speed as a safety feature. Hasn’t been used in quite some time. Incorrectly called velocity, it is actually acceleration.
//angular velocity in rads/sec = 2PI * m/sec * radians/meters
angVel = glm.twoPI * 0.277777 * mf.pn.speed * (Math.Tan(glm.toRadians(steerAngleAB))) / mf.vehicle.wheelbase;'''
Sorry to burst a bubble, but using a steering encoder at the wheel is not a WAS less based system - you are sensing a steering wheel angle. Any non-holonomic (vehicle with wheels that steer) with a steering wheel can utilize this. However a vehicle with a joystick or track driven - or even a 4wd are considered holonomic at the operator level.
The CMPS and BNO085 output angular velocity. AOG calculates a required angular acceleration, the integral of which is angular velocity. Take the 2, derive an error, actuate the steering system accordingly. That is what is involved in a WAS-less auto steer.