No, absolutely not.

1. It's my T's job to hold the line. No one can manipulate you if you don't allow it.
2. My T can't help me if she doesn't know the truth.
3. So called "manipulative " behaviors are usually rooted in deep seated unmet needs and play out in all relationship in your life--- so they need to be exposed and dealt with
4. My relationship with my T is deep and honest enough that I can say something like. " I'm doing x and part of me feels like i am doing it to get a reaction from you" or whatever

I think holding things back defeats the whole purpose of therapy