I cook, and I disagree with the assertion that a better knife makes you a better cook. Good knives are useful, but ultimately you're still going to produce crappy results if you're a bad cook with a good knife.
A bad dull knife bruises and smashes more than it cuts. If a first time cook was making a salsa, the one made with the good knife would be better as the tomatoes would be juicer and not all smushed.
The only thing a better knife does is save you prep time. Being a good cook is about understanding how different materials cook, when different foods are "done", how flavors work together, and how to improvise when things go outside the plan/recipe or adapt to novel situations.
Cutting technique is only important if you're a professional chef with actual time constraints and can't afford to spend an extra 30 seconds cutting an onion.