The reason for moving a vert is not about morphing a mesh or moving a lone point. Moving a vert moves the angle of the line of a poly specifically along a given edge. This allows for instance if the mesh *bends* in that area it will bend depending on the angle of said line/layout of polys. This is a big part of what people are referring to when they are commenting on the topology, not the number of polys so much but the direction of lines so that if/when the mesh twists, bends, etc.. during animation or movement it does so cleanly. Hopefully this clears some of this up. Having said that, Roygee gave the best/simplest answer from what I can see. Adding a new line and dissolving the unneeded would do exactly what one wants without a lot of extra steps. A little more then just sliding the vert but not enough to be a bother
There is even a video tutorial on exactly the method Roygee describes but I don’t remember where I saw it exactly. Possibly in one of Fugazi’s tutorials.
Btw RedSquare, there are reasons for creating (and even extruding) verts but that is a different topic
@Pen Those are good techniques for doing quick adjustments and might actually accomplish what someone needs when thinking of moving verts around, but the general idea of moving verts is to adjust the base mesh usually during final creation process before distributing/finalizing it. The techniques you are referring to are for adjusting a mesh after the fact for a specific situation. I hope that makes sense.
Of course I could be totally off base and misunderstood the purpose for the original question ;p