There are situations where the brain doesn't record what the eye sees. Basically it you take a quick glance the brain "fills in the background without recording what the eye sees". So if you have ever been in the situation of "where the f@@@k did that come from" that is probably what happened. The answer is to always take two seconds looking before reacting. I have had this happen to me twice fortunately without incident, I believe it is more likely to happen when tired.

Keith
2013 narrow bodied + 4 Ruby.