I can't comment on the manner in which the DM said this, because I wasn't there, but he should not be criticized because he said it. This is the way students are taught to do exits and there are good reasons for it. Even if you have a reg readily available reg, you could still fall in the water and get a mouthful before you recover the reg. Ordinarily, this isn't much more serious that a coughing fit, but an unexpected mouthful of salt water has been known to lead to some pretty serious accidents. When you are ascending the ladder, touching the ladder isn't really the issue, you should stay clear of the ladder until the previous diver is completely clear. I am sure the dive operator's insurance company would have a heart attack if they did not follow these procedures. The DM is not a jerk because he insisted on these procedures. Whether he's a jerk because of the way he insisted, well, that's another question.