Each NP-complete problem is in fact a family of problems. In the sense that you could compute an optimal sales route between a small number of cities or optimally pack a very small knapsack in your head.<p>I believe the point the posted article is making is that reasonable progress has been made against such problems of sizes that seem &#x27;large&#x27; in terms of normal human experience, through brute-force computation and clever heuristic tricks. That doesn&#x27;t mean they don&#x27;t scale in the expected way or that a true shortcut has been found.