Distance weighted interpolation in predictor steps vs corrector steps

I got stuck while reviewing the journal article "Accurate reaction paths using a Hessian based predictor–corrector integrator".


Why is the distance weighted interpolation done in the predictor steps, instead of doing it in the correcter steps?


Source: [H. P. Hratchian and H. B. Schlegel, *J. Chem. Phys.* **2004**, *120*, 9918](http://scitation.aip.org/content/aip/journal/jcp/120/21/10.1063/1.1724823)


