Yeah, it's most efficient to use stamina during 3x fever. But you have to already know whether you want to go for ranking or not because it's only 2 hours long.
The commitment, man.
I dunno, I found it helpful during the last event so I knew how much farther I had to go to get the ranking prize, but I can also see why it could tempt people to spend more (stamina and/or pearls and/or $$). ^^; Knowing you're just
that much off from getting into the next tier makes you think "Well, I'm pretty close already, so why don't I just go for it?". And then you get stressed trying to maintain rank, as you said... And it's sad when you fall just out of the range required because GAH sleep.
Although I might have no idea what I'm talking about, since I rarely go for rank and only actively did so last time because there was a chibi I wanted.
Ranking woes in SLBP? Haha, ramble away~ That's what the forum is for. xD