Having posted this and reading some of the replies, I had a frank discussion with hubby about our current approach. We see now how asking the question about bi m play can be viewed as an invitation to play that way...so we don't want that. We also would not want someone to compromise their preferences in order to take part in a threesome as in the way two4youinswa described.
I also pointed out to him that he is living in a world of double standards...it's ok for the ladies, but not for the men. Bi does mean BOTH after all...he sees how I play as a straight woman but from time to time do enjoy the taste and feel of another woman. But, I still identify as straight. Using wifes_toy's scale I fall as a maybe a 3. Hubby is a definite 0.
I think this was a breakthrough discussion for us. I love that the people here give us such interesting a fresh perspectives that give us reason for pause and sometimes a shift in mindset. I feel like perhaps his position has changed a bit...which is a very good thing.