This is a link to a thread about a situation at the track with a red flag and what could have been a really bad accident
Its 11 pages, you don't have to read it all to get the gist
http://rennlist.com/forums/racing-and-drivers-education-forum/907838-de-safety-red-flag-lucky.html
perhaps it would not be a bad idea to do a red flag drill at our TT/DE events
(what do I know, I am a newbie at the track)