On top of this, by knowing music theory, you will be able to look at any piece of music and be able to analyze it. For example, you will be able to tell where the bridge is by a quick glance, what the song sounds like, and also be able to easily find mistakes.

All the good rock, alternative and other popular musicians have a good sense of classical music. I know of many who have, or currently study classical music, and classical voice training, including Mick Jagger, Steven Tyler, Cyndi Lauper, Christina Aguilera, and Billie Joe Armstrong (Lead for Green Day). They have spoken numerous times about the value of knowing about classical music and theory.

Also, by knowing about music theory and they historical progression of music, you will be able to further explore in your compositions to provide for unique compositions that can define you on a higher level, rather than just the standard "norm" in the current music scenes.

Hope this helps.
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If all you want to do is to compose rock music, what you need is a guitar and a big amp. Some chemical substances are known to help too.

However, there is a chance your school program will open your mind to different -and better- music. So I’d say yes, apply for the program -with a little luck you will NOT end up composing rock music.
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And here is the reasons why:

Damn near anyone can pick up a guitar, learn three cords, and ‘write’ and ‘play’ rock music. It really doesn’t take all that much skill to do so. And all you have to do to write pop lyrics is have enough song-writing skills to rhyme ‘love’ with ‘dove’.

However, let’s say you want to write a fully orchestrated concerto, learning three cords on a guitar won’t get you very far. Try learning how to write and score music for 80 separate instruments, learning counter-point, half-notes, etc.

However, a truly gifted musician and composer who can write and understand a broad spectrum of music can create a rather unique rock sound and take rock to a higher level. Pink Floyd, The Moody Blues, ELO, Van Morrison, Paul Butterfield, etc. have done so.

But the general rock buying public isn’t interested in intelligent, original music and profound lyrics. If they were Leonard Cohen and John Cage would easily out-sell the Jonus Brothers and NIN.

I’m not a snub. I’m being honest here. There is nothing wrong with either genre and I get as much enjoyment from listening to David Bowie as I do Beethoven. I also am a big fan of intelligent, poetic lyrics (Bob Dylan, Leonard Cohen, etc.) and still, other times, I like to be rocked to the soul by Counting Crows or Rush or ZZ Top.

The point is, unless you want to try to take basic three-cord rock to a higher level (like out-doing ‘The Dark Side of The Moon’) then there’s little reason for you to spend a lot of time learning the skill levels required to play or compose classical music. You have to decide if you want your music to make people want to actually think or make them want to boogie down. It’s kind of hard to do both on the basic level of pop and rock.
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