Actually that was a simplified (poor) explanation - increasing MaxForceAtSteeringRack doesn´t decrease overall forces, it actually increases the amplitude of the forces. Ideally this setting would be the actual Max force at the steering rack a given car is subject to at its peak load, which can be measured via telemetry. If we set MaxForceAtSteeringRack to those actual values, the peak force (which is determined from both the FFB strentgh in the controller profile combined with in-game slider) will be at that peak load, and you will feel the wheel build up force all the way to that peak load / force.
The problem is, having such "correct" values would make your average G27 wheel feel really light most of the time, so the compromise we use is to set MaxForceAtSteeringRack at a lower value than what the car is actually subject to, allowing the FFB strentgh to peak sooner and thus making it feel heavier at lighter loads - but clipping the effects from any extra load from that point on.
Thus, if you feel FFB is too heavy on curbs and such (which you will if you actually have a 1st class wheel such as the Bodnar, or if you just prefer more feel rather than pure strentgh) it´s likely you will find best to increase MaxForceAtSteeringRack - which would not only lighten the forces at lighter loads, but also give you more amplitude without reducing the max force at peak loads so long as you set it within the vehicle´s actual force range. If you lower the FFB strentgh (be it from the controller profile or from the in-game slider), you will reduce overall forces while still clipping the effects from higher loads, which is the worse of both worlds.