Pre-Conditioning in Adjoint Solver Numerics

What does preconditioning in Numerics under the Design Tool option in the Fluent adjoint solver imply?

1) Preconditioning for the prescribed motion implies advancements for the prescribed displacements. A value of 0 yields the most aggressive advancement, while a larger value encourages more stable, albeit slower, advancement of the process for updating the prescribed displacements. A value of order 1 is typical in the event that preconditioning needs to be applied.

2) Preconditioning for freeform motions implies advancement for updating the freeform displacements. A value of 0 means that no preconditioning is applied, while a larger value encourages more stable, albeit slower, advancement of the process for updating the freeform displacements. A value of order 1 is typical in the event that preconditioning needs to be applied.