I can't find the post now, but someone emailed Shulgin a while back in regards to the 16mg overdose report & posted part of his response. I'm going to paraphrase from memory, so forgive any inaccuracies, and if anyone can find that post, please do & post a link in this thread.
The 16mg overdose report was the result of a subject undergoing some rather intense therapy regarding his childhood while on 2c-p. As a child, he was in an earthquake and a bookshelf (or something similar) fell on his legs injuring him. During said 2c-p experience, he relived the experience very vividly, including the pain in his legs. Hence the physical disaster terminology. Also, those are the subjects words.
That being said, 16mg is a hefty dose of this chem & not to be taken lightly. I've explored it at up to 12mg, and those experiences were quite long lived, but i probably will inch the dosage up a bit more as i become more experienced with 2c-p. The dose response curve for this one seems similar to other 2c's, however it is more potent. So whereas with 2c-e, the difference between 8 & 10mg for most people isn't that significant, but the difference between 16 & 18 is quite significant. With 2c-p, the difference between 3 & 5mg isn't very significant, but 7 to 9 is very significant. All of this is from my own experience and doesn't necessarily translate to everyone, but should prove helpful to most.