There is a script that comes with Vegas 5 that removes a specific effect from all clips. Look at the "Remove Timecode From All Media.js" script. I've pasted it below for reference. You can change the name of the effect hardcoded in the script to remove your cc effects. Just don't overwrite your original project file. :-)

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/**
* This script will remove all effects of a particular type from items
* in the project's media pool.
*
* Revision Date: Jan. 30, 2003
**/
import System.Windows.Forms;
import Sony.Vegas;

// This is the full name of the plug-in associated with the effects
// you want to remove.
var plugInName = "Sony Timecode";

try {
var mediaEnum = new Enumerator(Vegas.Project.MediaPool);
while (!mediaEnum.atEnd()) {
var media = mediaEnum.item();
var effectsEnum = new Enumerator(media.Effects);
while (!effectsEnum.atEnd()) {
var effect = effectsEnum.item();
if (plugInName == effect.PlugIn.Name) {
media.Effects.Remove(effect);
}
effectsEnum.moveNext();
}
mediaEnum.moveNext();
}
} catch (e) {
MessageBox.Show(e);
}