Isolate for Exclusion is a mesh control used for convergence. Specifically, it tells the software to exclude the selected from consideration in the convergence study. The only way this could help you speed up your study is if you restrict the p-order in the analysis definition AND if it so happens that software would drive the p-order of the element after the first pass.
That being said, what type of analysis are you doing and what results are you after? While you could go through the process or replacing a component with a idealized representations, it may be faster to just leave it in the model (depending on what you're doing).