I would like to add to this discussion. I'm using an older version (R10) and have been unable to change sketch dimensions settings (offset from object, text size, extension, etc)
Here are two images to illustrate my point. The first shows an absurdly large dimension which will crowd the work area.
The second image shows a situation that I've never seen before. I'm measuring two offest ellipses which were imported from a copied sketch. As you can see, the larger ellipse has a dimension of 0.5mm while the smaller ellipse has a dimension of 0.58mm
Any advice on this issue would be greatly appreciated.