Is this is a mechanical arm to hold a soldering iron that then can be moved around in an XYZ stage so you can move it back and forth to solder joints? This is what it sounds like you are suggesting. The act of using a soldering iron by hand has a significant amount of visual and tactile feedback that is really easy for a human to understand, but not one a robot will.
If so, then no, I would not use this. It is not useful, since if I'm assembling a few boards, its faster for me to just assemble it, rather than program and test assembly procedures with a complicated robot iron, not to mention any concerns of parts moving around mid process. If I'm assembling multiple boards, then I have someone with a wave solder machine do it for me, since their machine will do it much faster, and not require programming. This is an already well-established technology.
If you are looking for a faster way to solder parts yourself, look into the hot-plate/stove-top method. While I've never personally used it, I've heard good things about it.