I get super tired of having to scroll-to-the-top, when clicking on the title, last-updated, etc columns. Especially with a touch screen.
The post-sort default is to display your selected resource at the top (which is almost never what I want).
But ... if you first click on a rollup column (eg myTags, Author, etc) and then Title, Last-Updated, etc, it defaults to the scroll-top.
Apparently, the rollup type columns force a 'release' of your current selected resource.