It will do a wake lock every time it has to CHANGE the color. For example, if you have it set to go Red-Green-Blue-Red-Green-Blue..... when you have an email, missed call, and fb message, this will cause several short wake locks EACH SECOND.
For this reason, I have mine set to only show the color of the LATEST notification, so the color only changes if I get a new notification of a different color.