I would like to add a couple of additional thoughts.
I am not sure what the mean time between failure is of the HDMI port of the Chromebook, but one consideration is to buy one of these devices to reduce wear and tear. I may just get one and keep it plugged into the HDMI port of the Chromebook so this will take on the wear and tear instead. I still think avoiding the Chromecast dongle is the way to go to avoid leaving a chart up on the TV monitor when leaving the exam room.
http://www.amazon.com/Monoprice-8in...eywords=hdmi+female+to+hdmi+male+adapterAlso, I got hand holding from my local IT guy for setting up the VNC viewer but here is the link.
https://www.realvnc.com/products/chrome/1.0/connectguide/connect4.htmlI may have to do a bit more research to find the best HDMI to HDMI gadget, to save wear and tear. Also I ended up getting the Enterprise version of VNC viewer for chrome so I can maximize encryption to 256 bit.