People here are always telling you to listen first and become educated on a given topic before you speak, and you continually spout BS at every opportunity.
First off, going quickly on the track, while listening to an instructor and concentrating on your line, are all things that a skilled driver can do. You are not skilled enough yet to do it all at once, so you nearly drove off the track- plain and simple.
Your ego is preventing you from admitting that you made a mistake- a common problem with beginners. You drove beyond your skill level, and you found out what happens. Hopefully you don't do it again (in Turn 2 anyway).
Now, perhaps you could explain just how the weight of a Mustang's engine affects it's autocross performance? Thanks.