There are times when I'm detailing drawings that the cursor will grab an angular dimension from somewhere else on the page. It doesn't seem to matter if I'm trying to select a drawing view, a note, or some other dimension. The attached image shows an example (the black arrow represents the approximate position of the mouse). I was just hovering the mouse over the view, and you can see in the upper-right that it was highlighting the angular dim for selection. If I were to left-click at that point to try to drag the view, it would instead select the angle and drag it.

For what it's worth, I'm using 2014 x64 SP3.0, but have had this issue since SP1.0.