Yep, I went through that with one of my green horses just this summer. She had been ridden before (and had some horrible habits because of it) so I progressed her a bit quickly up into the curb. I mean, after all, she did have 30 days "professional" training on her already *eyeroll*. I rode her in that for about 5 minutes before I decided that she wasn't anywhere near ready for that so back down to the snaffle she went. After a few more rides in the snaffle, I felt she was ready and transitioned her up again and it went off without a hitch. Nice and soft, responsive to the flick of a rein, and relaxed.