What happens when a flourescent ballast "goes out"?

It seems to me that a flourescent ballast is probably just a transformer
and 
a high-voltage electrolytic cap.  And when it "goes out" it's probably 
because the cap failed.  If these are true, could I just replace the cap
and 
make it work again?  Assuming (hate that word) of course that I could get 
the ballast open.  What thinks the group?  Please offer whatever laughing 
criticism or encouragement you feel is appropriate.  I do not need a fire 
hazard in the kitchen...

Many thanks,

Dave