The Pega-IAC ruleset is actually NOT needed in your application in anyway. You may need for developers so when I need to see something within the Pega-IAC ruleset I just include it in my AccessGroup in production rulesets.
The Pega-IAC ruleset is used primarily for the PRGateway functionality of testing the connection, downloading the PegaInternetApplicationComposer.js and configuration of gadgets. This is done with SOAP services and there are many of them with different package names. Each of these specifies an AccessGroup of IAC that contains the Pega-IAC ruleset in the production ruleset list.