Here is a link to a very similar discussion started just a few days ago for an 8th grade girl. I’m sure others will have things to chime in regarding your S’s particular strengths, but many things mentioned here would be the same. Haven’t seen Whiplash yet, but your S’s experience does not need to resemble that in any way. Most of our kids had fun pursuing this path - even though they work very hard.
http://talk.collegeconfidential.com/musical-theater-major/1758692-early-to-the-party-hs-freshman.html#latest