It is absolutely worth keeping track if for no other reason than to keep them honest and accountable. I wish I didn't feel like I can't trust Kinkoid, but they've had a history of manipulative behavior/language or even downright breaking promises. Some examples...
Claiming that PoA girls would be exclusive, then making Lupa's Mom, a girl many players paid 7200/1200 kobans for, available in the pachinko during the last anniversary.
Claiming that every girl in the game would eventually have 5 affection grades.
When Legendary Days was new, claiming that the girls might never come back and also refusing to call the drop rate high or low but rather "adjusted to the event duration". Of course, we all know what that translated to.
I've been keeping track of my drops since the patch notes (spoiler: it's down to 2/12, or 16.67% for me since then) and will continue keeping track of them until they either return to normal, it becomes clear that I'm just having an unlucky streak, or (if it turns out they actually did lower the drop rate) Kinkoid admits they lowered it. I encourage others to do the same, lest this be swept quietly under the rug.
