Hello there!
Allthough using Blender for quite a while now (should be around 10 years) i never had an issue when selecting vertices. But playing around with Blender at home the last days i encountered a behaviour that i never noticed before. As i use Blender 2.64 on my production computer (where i never came upon this issue) and 2.68 at home i assume, it has been introduced in one of the last versions.
What happens is this: I enter edit mode of an object. All right. I select a vertice by clicking on it. All right. I select another vertice by clicking on it. The previously selected vertice gets deselected and the newly clicked vertice is now selected, as expected. I hold shift and click on another vertice - now two vertices are selected. Everything fine.
But now something happens, that is completely new to me. When i click another vertice now, without holding shift, i would expect the two selected vertices to be deselected and the clicked vertice to be selected. But instead i now have 3 vertices selected. And more than that: this behaviour from now on is the default: When deselecting all vertices by pressing a and starting to select again, i do not have to press shift to add vertices to the selection, the get added automatically.
This may be usefull in some situations, but not in mine. I have no idea if this is the intended behaviour or a bug, or if i can revert that behaviour to what i was previously used to (clicking a vertice without holding shift deselects all selected vertices and selects only the new one).
As said, i’m on Blender 2.68, Mac OSX. Hope someone can help on this.
