Lenn,
This link (CA Single Sign-On Integration - CA Identity Manager - 12.6.8 - CA Technologies Documentation ) provides the published (aka product guide) details on integrating SSO with Identity Manager. The concept of "tight integration" focuses on defining SSO Domain policies to secure sign-on to an IME and the management of the IME admin tasks, along with localization of the browser content. A "loose integration" with SSO would only provide authentication services to access the Identity Manager consoles, ../iam/im/IME or ../iam/immanage.
The SSO Integration topics in the Identity Manager Configuration Guide might raise as many questions as the answers provided, so maybe you can share what specific integration you had in mind.