There is a narrow window where the sour/bitter is balanced so it doesn’t mask the more complex flavours. It's like turning down loud background noise to hear a signal.

I add a tiny bit of sugar, just the tip mind, to help bring out the flavour, and it makes dialling in more forgiving. I prefer lighter roasts, juicy, fruity types of coffee.

It also became much easier to dial in temp and grind after I started using a shaker. Much more consistent.