we should talk about this. I think there's value in rolling up sets. sure, it's impossible to go from 5 1-minute samples saying that 10 distinct events occurred each minute and be able to know how many distinct events occurred over that 5-minute window. but, knowing that across 5 distinct windows I had a min/max/avg of 10 unique events during each window seems valuable to me as a user.

by not rolling these up we introduce a special-case w/rt retention where one type of metric is unavailable after a few days.