My idea for the graph compare; I imagine an interface much the same as exists under charts currently. However, instead of a tags drop-down, you can select more than one (e.g. check boxes). The chart then would update the legend text for each enabled tag (e.g. “Fall asleep hour - #tag1”, “Fall asleep hour - #tag2” or "Snoring - #tag1, “Snoring - Tag2”) and draw a separate line (different color) for each selected tag.
In this way, I could compare my Snoring when I’ve had #alcohol to when I’ve been #drunk, or #bed vs. #couch.
Obviously some tags would provide nonsensical comparisons, #alcohol vs. #couch
But that’s not really different than now. It’s up to the user to find usefulness.
support conversation with James