Luckily all these utilities doesn't give you back your .fla ...

The only good way is tacking backups ...
Every half hour you save your .fla
Every hour alternate the file name and dir location ... (another physical hard disk will do fine)
If artwork is done or just when you feel it ... take a real backup.
Fla's you didn't use for a while ... burn them on a CD ....
All these little nifty tools gives you only a timeline of one layer ... so you probably won't learn that much from it ...
If you really want to learn from .FLA files go to flashkit.com and download some open source fla's, but really don't use the trick of ... "i accidently erased ..." it's rather old and no one really believes it ...
My 2cc
Greetz
Knuff