I don't use any browser caching on any of the 7 browsers I test with.
desktop: Chrome, Firefox, Edge, IE11.
mobile gets the cache purged each time the browser is closed for Chrome and Firefox. iOS Safari is the fun one :/
Testing as I write is done locally, so no network caches there.
Testing on a live forum is done as each change gets merged and documented, and then placed on to live forums such as ubbcentral, ubbdev, wip, my personal forums and a few client forums who choose to run managed snapshot versions.
Your hosting is done through GoDaddy, am I correct?
You also.mentioned running locally with Xampp. Are you using fresh databases or a database from an import?
What are the results of the ubbtest script when you ran it?
Have you looked at your php.ini report to see if it's reporting the same values your told it to use in the php.ini config file?
I'm curious here. Especially since you have a medium sized forum, and it was exhibiting the same results as a forum placed on shared hosting with very throttled back resources. Such as a medium sized forum on a $2.99/mo shared hosting plan would do.
