I have never wore a harness hunting in the 5-6 years I have been into hunting. after reading some of the posts we had just a couple weeks ago about the fella that had to be on life support and took him self off. I borrowed a cheesy harness from a guy at work (he tells his wife he wears them and he doesn't) so I started using it, and last week I went to Academy and bought a nice aftermarket one for like $50-60. Best investment I could have bought. They do not limit mobility that much, gives me a peace of mind that if I do fall i have a better chance of going home that day alive to see my wife and son again.
No deer is worth your life!
Hook Up! At least for your family's sake.
Good for you and I would tell your buddy no more hunting with him unless he wears harness, period. If he kills himself while hunting with you, you will be the one to have to tell his family about his stupidity.