As a solo diver, I'm not sure who I'd give a hand signal to... other than my pony bottle. However, when I do dive buddied up I have noticed a lot of confusion regarding the hand signal for the safety stop.
As for divers lying about their experience level, I remember two who told me the truth when I was diving at Cousteau's Fiji resort. My first buddy made it clear that he wasn't going to follow any of the rules put forth by the DM. He began descending past 150 ft and I signaled the DM to go down and get him and I'd join the rest of the group at 60 ft. Although he didn't lie, it was a lousy dive!
The second buddy that trip was a new diver who said he was a real air hog. We did surface after about 30 min on a dive I would easily have gone 60+ min on. However, he had been direct and honest so I knew what to expect. He was extremely apologetic after we were back on the boat, and I told him he shouldn't be as he was clear in telling me that from the beginning and I had a nice dive with him.
As for divers lying about their experience level, I remember two who told me the truth when I was diving at Cousteau's Fiji resort. My first buddy made it clear that he wasn't going to follow any of the rules put forth by the DM. He began descending past 150 ft and I signaled the DM to go down and get him and I'd join the rest of the group at 60 ft. Although he didn't lie, it was a lousy dive!
The second buddy that trip was a new diver who said he was a real air hog. We did surface after about 30 min on a dive I would easily have gone 60+ min on. However, he had been direct and honest so I knew what to expect. He was extremely apologetic after we were back on the boat, and I told him he shouldn't be as he was clear in telling me that from the beginning and I had a nice dive with him.