I've been kinda wondering about this too, most of my negatives used to require hours of darkroom struggles and sheets and sheets of paper to print decent... but my most recent negs (and the one that I submitted to the exchange) printed beautifully with no dodges/burns. I tried a few things, but the "straight" print was the best - sweet and easy!
So, does this mean my technique is improving, or just a coincidence? Should I discard the negs that won't print like this, as inferior exposures?