There's no AJAX call in a SPA if all I did was close a detail side-pane to get back to the listing. The AJAX call goes on in background if I saved a modification and I can continue to use the app as it runs. And when I open a detail, at least I'm not watching the whole damn app reload and reconstruct itself from scratch for the 1000th time, and need to download just the data and not the whole bloated HTML mess.