I saw that site a year ago. I emailed the fellow to warn him of the hazards. He replied quite intelligently, if I recall. I think he said he would quit using it long before he thought it might break.
Still risky for sure, especially since he may not understand tree and wood strength and decay, etc etc. I wouldn't trust that limb more than a year after the tree was cut. He did say he would lower the anchor on it, and or back tie it off if he could. I should email him again to remind him that it is time to quit climbing on it.