Agreed, 100%. My co-founder and I read all of Paul Graham's essays before starting our current company [1], and it really helped us get a good intuition for the kind of work that gets you closer to product-market fit. (Good work: direct sales, building MVPs. "Play" work: branding, getting coffee with people outside your industry, spending time on HN.)

It took us 5 pivots and a year before we saw any meaningful revenue, and it would've probably taken us three times as long w/o those essays. Three pieces of "book knowledge" really helped in making hard decisions on the journey so far:

1) As an entrepreneur, you have the ability to make excuses and, say, welch on a sales call. ("I am not feeling well; I had better sleep in.") You can exercise free will in this manner, but doing so is a complete moral failing. (Steli Efti)

2) Never buy risk unless you're being adequately compensated. Before you have product-market fit, the riskiest thing to do is to work on a project with a long feedback loop. Structure your projects so that you can learn if it's working or not ASAP. (Alfred Sloan)

3) Keep track of your runway, and don't forget to exercise :) (PG)

[1] We read them because they were super fun to read - it didn't feel like homework or due diligence! PG's Twitter is also wonderful.