For years, my tablet was an Android device. If some text in Adobe reader was too small, all I had to do is zoom over a paragraph using two-finger spread. The focus stayed on the paragraph immediately after the zoom. Does not seem like a huge computational problem: first get the coordinates of touchdown, then zoom, then re-center to keep the original touchdown in place. So, why or why does the same Adobe Reader wants to jump to the center of a page after zooming on Surface Pro? Now, it’s two actions: first two-finger zoom, then one finger slide back to where you were reading. And, if you happened to zoom too much, your original spot is not that easy to find. Perhaps, there is a setting somewhere in the deep preferences corners to solve this, but sure not easy to find, if it is there.