This is I think a question of parenting and educational philosophy. My kids have been nowhere near as talented at age 13 as your ds, but I think that's in part because circumstances and parenting philosophy led me not to put them in a high-intensity enriched environment that is rife with high expectations from others. This was a conscious choice. I grew up on the edge of the same musical sphere in SW Ontario as Corey Cerovsek, the ultimate intellectual and musical prodigy, and watched as he and other prodigies developed. I saw all the possibilities for hot-housing young musicians and how they played out. I knew that wasn't what I wanted for my kids. I wanted them to have balanced, healthy childhoods, so that even if they decided at age 18 that they never wanted to play music again, they wouldn't be full of regrets about all that they gave up of their childhoods. I wanted them to indulge their "normal" sides: obsessing over a new video game, spending crazy Saturdays playing Balderdash, going on backpacking trips, learning mountain-biking tricks, hanging out with friends for Harry Potter movie marathons.
My eldest was essentially teacher-less for quite a while during adolescence and until age 17 had only a lesson or two a month with no regular ensemble experience, because although everyone could see that she had immense potential, I did not believe that potential comes with the obligation to fulfill it. I admit that our rural situation conspired to keep the demands on her at bay, so I don't take full credit for achieving that balance myself -- it was partly just the result of where we lived. But I knew that if she was going to end up in a high-pressure intense competitive environment I wanted her to come to that fully informed, as a mature human being who had purposely chosen that situation for herself and knew what the alternatives were. I didn't want her to choose by default, just because those around her kept funnelling her into what they thought would bring her more success sooner and "realize her full potential" as if this were a law of the universe that it was a sin to break.
She is an intense perfectionist, extremely obsessive and driven when she puts her mind to things and is in an environment that feeds her obsessions. I think if she had been pushed in a competitive direction she would have ended up stressed and eventually burnt out. At age 17 she sought out a taste of that a more intense environment: weekly lessons with a big-name teacher, high-end competitive orchestral experiences, and flexible schooling to give herself the chance to practice a lot. She ended up making it very intense indeed: practicing 6-8 hours a day on top of rehearsals, occasionally up to 12 hours a day of playing, carrying a full load of senior math and science courses through distance education, living on her own, touring with her orchestra, doing a bunch of auditions. She absolutely loved it: I've never seen her so happy and energized. She obviously didn't have the kind of environment that set her up for recording the Kabalevsky Concerto with a major orchestra as a teenager, but she isn't mourning the loss of recording contracts. And she knows that any stress she puts herself under is a choice, and that other choices do not connote failure on a preferred or expected track.
I would encourage you to look long and hard at your ds's musical path and the expectations that he's immersed in. If you change nothing, the pressure is only likely to get worse over the remainder of his formative years. If your ds is less happy and more stressed in a period of intense work, rather than more happy and more energized, I would suggest that the default trajectory is not creating the right balance, and that it may be important to start sometimes saying "no" to opportunities, to gently take the foot off the accelerator, to occasionally apply the brake. I don't think the world will end, musically or otherwise, and it will be important for him to see that it doesn't.
Good luck!
Miranda
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