I have a routine that I have always used when hiking with a group of more than two people. I call it the 10 minute rule. Dates back to my days as a boy scout under Scout Master Robert Parker. Every ten minutes you look back until you see the person that was behind you. They know you are looking back to see them. If all is good you wave at each other and then get back to hiking. If not they can signal you that they need help. Each person in front will know something is wrong when they don't see the person behind them within 5 minutes of the 10 minute mark. This way with a group of seven hikers the fastest hiker will only get about 1 hour ahead of the slowest hiker.
I hope this hiker is OK and waiting to be found. My thoughts are with the whole hiking community. I hate to hear of a fellow hiker not coming out.
