caring for tack

I recently bought new leather bridle and reins, and used neetsfoot on them one, but they seem to still be pretty stiff. How often should I treat them, and how soft should they actually be. Is there such a thing as over oiling? The headstall is pretty thick, and husband says that is why it's so stiff, but it seems really hard to me.

I have a saddle that doesnt need oiling, so I'll tell you how I treat my bridle: After every ride, I clean it with leather cleaner. I find that works pretty well; I use Leather Therapy. I've experimented with a LOT of different leather cleaners (literally, we have about 15 different kinds in the garage) and this one really works well. As for how often to oil, I'll be checking in to see what people have said myself;)