Anytime a person connects to the SSL portal and tries to click on a web resource that we have associated to a ticketing system, the page does not render correctly, the current fix is to refresh the page. The source codes ends up being different from the original and the refreshed stages of the rendering process.
Along with caching settings, you can try compression settings, PTP (Pass through proxy), JSAM, WSAM, or if needed NC.
httpwatch or fiddler can help diagnose some web issues as well. They log all of the traffic that is being picked up by the browser.
If you still can't find a solution that works for you I would suggest creating a JTAC case.