Part of our workflow is to take the GeoTIFF and turn it into a PDF with the CAD overlayed. We choose to do this in Bluebeam because of the way it handles vector CAD files and the 3-point alignment that allows you to achieve spot on alignment between the image and the CAD.
This tip is for anyone that has had trouble opening an ortho in Bluebeam (and Acrobat for that matter) and is having trouble with either the file not opening or opening and not displaying properly. Working with the Bluebeam engineers we have figured out that unknown to them that the software seems to have a problem with a 50,000 pixel barrier. If your PDF software is having trouble then try downloading the 4in/px ortho. I know it seems like a low resolution, but the quality is good enough to create a great CAD Overlay.