The crafting talisman only increase the chance of success not the actual skill, either normal/exceptional or only normal or exceptional. They are great for leveling crafting btw, use them to increase the chance of success high enough to make something cheaper sooner and then remove it to be able to craft that item longer.
The Talisman of the Fey should increase Stealing by +10, look at your skills in the ferret form to verify it actually increases the skill rating.