That might cause flashes or another anomalies in the rendered material. Now that the preliminaries and the rendering issues are out of the way, a few brief words about these two small but powerful filters. After Effects has the ability to enable motion blur, but it is a global setting and AE calculates the blur that its preset algorithms specify. ReelSmart Motion Blur has the ability to set a variable amount of blur as well as removing blur from a clip. The filter works by calculating motion between two successive frames within a clip and then applying blur, based upon the motion it has calculated.
Operation is simple.
The filter, though, requires a video layer from which to extrapolate motion. Since that will be the clip to which you are applying the motion, you need to drag your clip from the Browser to the Get Motion From well. Then, there is only one parameter to adjust. It's very simple. Then render and check your results.