Hmm well...........
The only problem is that some people are quick to find new posts and quick to reply. Somebody may be already typing a reply to your original post (while you're editing it), and they may be actually quoting your original post. See what I mean?
I could possibly change it to 5 min... but I don't know if I want to stretch it any longer than that.
There is however another solution. Before you make your post, simply "Preview" it, and it will show you exactly how it will look when posted. It will be just like posting it (but it won't actually post until you confirm). If you don't see the "Preview Post" button, simply click the "Go Advanced" button, and it will give you that option.