I have a problem with how the LDFs are generated when all the losses are paid. In these situations, the incurred LDF is 1.00 - shouldn't there still be an IBNR element to the LDFs?

In most situations, several years will pass by before all claims within a policy period are closed. At that point, it is unlikely any new claims will be reported. Loss Forecaster will set the default LDF to 1.000 for any period with all claims closed that is over 3 years old.

However, there may still be reason to allow for future claim development on reopened claims. Loss Forecaster allows the user to override the default development factor of 1.000 with the appropriate benchmark system factor. This system factor will include potential future claim development for the policy period.