I used this mechanism für a DPS meter. It reads out the combat log using the same parsing function as combat analysis and then saves it to a plugindata file. At the same time another Application written in Java reads that data and sends it via a Server-Client TCP connection to all connected raid members and saves the data in another plugindata file which can be then visualized by the plugin.
That's pretty cool. Unfortunately it requires everyone to trust an external executable, get Java working on their system, configure their firewall, remember to run the external application... Which necessarily limits its popularity. I've thought of using user chat channels to share data, but it would require the user to click a shortcut each time data needs to be transmitted.