Well, sort of. It can help you keep your face angle throughout the stroke. However, if you're aligned wrong at address, you've got some problems. The Edel Putter is fitted so you're at 0.0 at address (or like 0.1 or 0.2). I had a SeeMore putter and was aimed 1.1 degrees open at address and then 0.5 at impact. So I was doing an okay job of keeping the angle, but couldn't aim it straight at address. Thus, I wound up going back to a putter with more offset and going back to working with my LPAS (Laser Putting Alignment System --- which you can get for about $40). I'd probably suggest that, if not getting an Edel Putter and that putting tutor thing that Pelz has.
The problem I have with things like the putting arc is that the putterhead is pressing against something. So when you take it off, and when the mind's memory has worn off, I think you're more likely to yank the putterhead too far inside. And like I said, it's more important to have the face square at impact than to have a great putting stroke path.
3JACK