title_body: Would 2 small V60 brews (1 cup each) be less bitter than 1x large (2 cup) brew?
upvoted_answer: You'll definitely get a less bitter and possibly sour (underextracted) brew when dividing up one 40g dose between two V60s if you don't adjust the grind.
  
  As you point out, the lower contact time of the 20g of grinds will lead to less extraction, and thus less bitterness, and possibly under extraction. This is just a characteristic of pour-over brews (as opposed to immersion brews) - grind size (and uniformity) is directly related to contact time and thus extraction, so the two variables can't be independently manipulated.