Apparently any FIRST page you access, will be kept in the DOM, even if dom-cache is set to false (well, it's already false in the configuration..).
Example:
I access this page 1st:
<body class="ui-mobile-viewport">
<div class="ui-page ui-body-c ui-page-active" data-dom-cache="false" data-role="page" data-url="/Mobile/User/Home" tabindex="0" style="min-height: 965px;">
<div class="ui-loader ui-body-a ui-corner-all" style="top: 482.5px;">
</body>
Now i go to this page:
<body class="ui-mobile-viewport">
<div class="ui-page ui-body-c" data-dom-cache="false" data-role="page" data-url="/Mobile/User/Home" tabindex="0" style="min-height: 965px;">
<div class="ui-loader ui-body-a ui-corner-all" style="top: 482.5px;">
<div id="user-search" class="ui-page ui-body-c ui-page-active" data-role="page" data-url="/Mobile/User/SearchView" data-external-page="true" tabindex="0" style="min-height: 965px;">
</body>
And now if i click to go back to the first page, even tho i'm saying i do not want any dom cache, the first page will simply be displayed again, and so i get a cached copy instead of a new one.
I can navigate all over the entire site, and it will always be kept in the dom as invisible, and then just be displayed if we ever navigate back to it again. All other pages get added and removed from the dom normally as we navigate around from page to page, it's just this 1st page.
If i would have navigated to the 2nd page first, then this page would have been eternally cached in the dom.