In your life, salsa dancing ability is definitely not the sole metric you wish to be optimizing for.

Things you presumably want to optimize might be something like personal happiness, bettering the world or wherever you find meaning.

If one truly wanted to drop resources into optimizing salsa ability, I'd imagine filming the dance floor from a few cellphones every week, uploading the video to youtube and paying a few experts on a salsa forum to give the dancers a rating and feedback would give a somewhat valid metric that you could go about tracking, quantifying and optimizing.

But I presume that that is not the primary goal of most salsa-goers. I guess that people go to salsa dancing nights because they are fun, good exercise and you get to socialize with a group of guys and girls who want to dance with girls and guys.

Can you try tracking happiness? Sure, why not. Have a prompt to record happiness appear at random intervals, or write a journal to note big highs or lows. Then questions like "do things like salsa increase my happiness more than things like video games" or whatever become addressable in a slightly more informed way.

I agree with you that your mind should not be on contrived proxy goals while you are salsa dancing. Better to be enjoying the salsa. But I disagree with the implication that because many metrics are tangential to the 'true' goal, careful measurement is flawed. It it still the fun/happiness that you care about, just now you are doing a smarter job of tracking it.