It is better to create custom properties for your nodes (say AlertRecipient). You can reference the recipient(s) as a macr instead. ${Nodes.AlertRecipient} instead of hardcoding. You can multi-edit the custom property from the web console. It is much easier to manage from the web console rather than edit every alert
You may also want to check out the free Alert Central product, which is specifically designed to manage on call rosters.