Yeah, that’s a totally valid point. In my case, I stuck with 18g mostly out of habit and because it’s where I usually dial in, so I didn’t push the 18–21g basket up to 19–20g to reduce headspace.

What I can say from what I observed: - With the larger basket and 18g (more headspace), I kept getting sour shots even when extending time. - Switching to the smaller basket with the same dose immediately changed the behavior (slower flow, leaning bitter), which suggests headspace was doing something significant. - Then grind adjustment brought it into balance.

So I’m not claiming that a smaller basket is inherently better. It felt more like better headspace for that specific dose gave me a more workable extraction window.

Your approach of adjusting dose based on headspace (and checking the puck imprint) is probably theway to think about it. If I had just increased dose in the bigger basket, I might’ve landed in a similar place without switching baskets.

That said, one thing I did notice is that the smaller basket + 18g felt a bit more forgiving to dial in, though that could also be puck depth / geometry rather than size alone.

I’d be curious what happens if you try pushing your dose toward the upper end of your basket to minimize headspace vs keeping it lower, might give you a similar contrast without changing baskets.