JRB'S THEORY ABOUT THEATRE AND ACTING(lol)
I do not differentiate plays from musicals from opera from ballet--it is all theatre to my mind. You are onstage telling a story. It does not matter to me if the devices used to tell the story are movement/dance or speaking/singing and to what degree of technique is being employed.
I personally dislike that we identify the triple threat by acting, singing, and dancing. I would prefer speaking, singing, and dancing. Odd? Yes, perhaps. But acting is the foundation that must be in place for all 3. And, when you perform in a musical, your acting shouldn't alter when you suddenly switch from speaking to singing or from movement to dancing. One is acting at all times--even when not speaking, singing, moving, or dancing.
Now, if I only I could perfect this myself!! =)