While I agree with a lot of this, I do have a couple of qualms:
1) Looking for a shortcut isn't always a fruitless endeavor. Say you're trying to lose weight. Conventional wisdom tells you to exercise more and eat less. That strategy seldom works in the long term. In this case, the shortcut, whether it be veganism, paleo, or whatever, can serve as both a better strategy than CV and as a motivator. Trying new things is fun!
2) Furthermore, what if your system and your end goals no longer align? For example, I used to study Korean because I lived in Korea. I started my studies as soon as I knew I'd be moving there. And though I had a reasonable amount of success, I eventually gave up. Not because I thought it was an impossible language, but rather, I didn't think the time investment would be worth the payoff. So I stopped training and "failed." Yet in the grand scheme of things, I don't see it as a failure.
Like, it's cool that you're eating sardines, but what's the real payoff? If you're enjoying the process, great — that's enough to make it worth continuing. However, if it's an ordeal you're putting yourself through daily for no reason, I have to wonder what the point is. (Perhaps I'm doomed to failure because I ask too many questions.)
In any case, good luck with the sardines :P