For each project, you currently select the Structural Analysis Option you want (Linear or Non-linear) and possibly a sub-option (Guying or Attachment Non-linearity). These settings apply to all pole structures in the project.
You can now choose to over-ride the project level setting for this and specify something different at individual poles. This option is available through the Structure Details Dialog and contains all the same options as at the Project Level. Simply checking a CheckBox enables you to set different Structural Analysis Options for this pole.
This option can prove useful in diagnosing difficult poles while using the Non-Linear Analysis method, or simply for comparison purposes.