Dealing with Camera Flashes in Smoothcam'd Footage

I wanted to post a quick video editing tip that I discovered while trying to stabilize some wedding footage in Final Cut Pro. The "easy" way to do this is to apply the Smoothcam filter to the clip. However, if the footage includes frames with camera flashes going off, the optical flow analysis used by Smoothcam frequently has problems analyzing the footage, and usually winds up adding sharp jumps right around the time of the flashes.

Here's the workaround I've found. I'm assuming you've already got a FCP sequence with the Smoothcam filter applied.
1. Right click (Ctrl+click) on the clip in your FCP sequence.
2. Choose "Send to -> Motion" from the menu.
3. Choose the filename and directory to save the new Motion project as.
4. When Motion opens up with the new project, go to the Motion Layers window and select the clip (which will be underneath a 'Group 1'). Make sure the current time is set to the beginning of the clip.
5. Go to the Inspector tab, and then the 'Behaviors' tab under that. You'll see the "Stabilize" behavior listed.
6. The key to this workaround is to add "trackers" to specific points the scene background that retain their contrast even during a camera flash, and also don't get obscured by foreground objects during the action. Click the "Add" button next to the Tracker label.
7. There should be a "Tracker 1" listed below in the Stabilize behavior's inspector. Click on the "Tracker 1" line to make sure you can see its location.
8. Drag the tracker's crosshairs to a place in the image where there's a high-contrast intersection. If you change "Auto-zoom mode" to "Edge", you'll be able to better see the places that Motion considers "high contrast". It's best if they are an intersection of two somewhat perpendicular lines.
9. In order for rotation and scaling smoothing to work properly, you'll want to add at least one more tracker, using steps similar to steps 6-8 that you used for Tracker 1. Even more trackers wouldn't hurt at all.
10. When you're done adding trackers, click the "Analyze" button next to the "Movement" label. Motion should start analyzing the whole clip.
11. Save the Motion project and exit back to Final Cut Pro.

That should do it! Hopefully Apple will eventually fix their optical flow algorithm to ignore camera flashes.