I was working on Fedlet setup with OIF 11g. I could not get to see SAML assertions in Fedlet debug logs, I don't know why. The goal is to look at the SAML request and response for nameid and other details.
So here is the simple way to get saml xml's. One should be able to see the SAMLRequest and SAMLResponse in http headers while testing the federation URLs in browser.
Use the tool https://rnd.feide.no/simplesaml/module.php/saml2debug/debug.php and paste the SAMLRequest encoded data and click the Decode SAML Message.
Another one here, http://openidtest.uninett.no/samldebug
The same holds true for both SAMLRequest and SAMLResponse data.