Trumpy,
As the safety guy at work I agree with you. It always helps to have another set of eyes looking at something. They might see something that is out of your eye sight, or that you cannot see. Also in case something happens there is someone there to help out.

For example I wrote a procedure on how to use the eye wash and emergency shower. I wrote in there that if someone has to use this that someone needs to be there with the person. One to help if needed and two for moral support.

Unfortunately just last week we had someone get acid in their eye. There was an eye wash station 15' away and a clear path to it. This eye wash, while do close, is actually in the fittings department. Since this employee works in the tube department, he was more familiar with the layout of that department. His first instinct was to go to the eye wash station in the tube department. Over 100' away and with several obsticales he had to go around. This is just an example of how someone does not think logically when they are injured.

If I might make a suggestion, maybe you could offer to management that the safety observer does not have to be a line mechanic. Maybe someone who is paid cheaper, but is trained in first aid. This may not be the ideal situation, but you would still have your safety observer, and management would save money.
Scott