Okay, so I've figured this out. Hear me out on this. For choice #1, you have a 2 in 3 chance of picking a goat. So, for 66% of the time, the door you've chosen is a goat. The host then shows you the other door with a goat, which leaves the final door - the car. So the probability of getting the car if you always switch doors is 66%! The overall probability cannot be changed to 50% because, if you first pick a goat, the probability from that point on that you will get the car upon switching is 100%! (And 100% x 66% is still 66%!) The other 33% is what happens when your first choice of door happens to be the car, and given the opportunity to switch, you switch. So Marilyn was right! (And consequently, the probability of getting the car if your policy is choosing not to switch, is 33%.)

One way to overcome the line-ending problem when working on multiple operating systems is to use your revision control system. For example, Subversion can be configured to automatically checkout files with the correct line endings based on the platform on which you are running. If you check-in a file on Windows using CRLF line endings, then checkout the same file under Unix, Subversion gives you LF endings instead. See here for further information: http://svnbook.red-bean.com/en/1.4/svn.advanced.props.file-portability.html