Actually, if you look at the diff offered in the production version of the SVT and the diff offered in the new 2001(possibly new Cougars too) Mondeo you will notice that the size of the diff gears was increased drastically...maybe Ford realized there was a problem with the durability of the gears...
Not every diff that has been blown has been due to excessive wheel spinning and the like, there is a particular case that Terry H mentioned where the diff blew in a routine 1-2 shift.
