My T has told me that if she isn't comfortable with a question, she will just tell me that she isn't comfortable. Same goes for me.
But, then again, I'm extremely careful asking her questions. Being told "no" often causes me a lot of embarrassment, for some reason.

Personally, I wouldn't ask my T something like that. Then again, she would ask me something like that... It's your call. The worst she can sa is no, right?