How silly was I. Here are the evidences:
June 12 -- passed Bitter Chocolate Strike CSP 2.25x. "Now with the crappy 2nd gen cab I can only do BPM 350 boost."
June 24 -- "I suddenly find BPM360 boost too slow and BPM300 intolerable."
August 30 -- Passed perditus†paradisus CSP 2.75x with an exhilarating 6:1 fast-slow ratio, a score of 550k. Lowest ever passing score.
Early September -- Every play ended up with notes overwhelmingly hit too fast. Change in offset (this is nice to have btw) helps nothing.
What happened?
Well, a closer inspection on the captures reveals the answer that took me too long to figure out: the damn boost is gone when I played perditus†paradisus. I has been using the default option since July till recently, and I played so bad in the period (not over) that I almost give up on playing any further.
In Bitter Chocolate Strike the speed was 2.25x BOOST, an effective speed of ~BPM560, slow but not intolerably slow even in the usual (i.e. good white cab) standard. And perditus†paradisus? Without BOOST would be BPM470 but if boosted would be close to 700, doable on white cab in the past (or rather, very comfortable for these hard songs), but very susceptible on this shitty cab.
Going back to what I said, I felt BPM350 BOOST comfortable in this cab, which is effectively BPM525, so BPM470 is rather slow in such standard. Together with the fact that my brain is so used with the BOOST flow that ended up with the historically low passing score. (Another possibility is that I changed my sneakers and perditus†paradisus was played in the first credit with the new sneakers, but the thickness of the new pair is similar to the old one so I don't think it's too much of a problem. As a contrast it took me months to get used with my last pair of sneakers.)
I finally realized and corrected such error last week and the result is clear. I started getting A+~AA- consistently across warm up levels (i.e. 13-15). So I started experimenting about the optimized setup seriously this time:
- Speed: BOOST is a must, now I say firmly say that. The problem is that I don't bother the extra cost for premium and BPM350 BOOST is too narrow of a range to get without the 0.25x multiplier. I found BPM380 (e.g. 御千手メディテーション or Possession) barely doable and BPM400 BOOST too much.
- Note colors: the sole reason I can't use higher BPM is the existence of unreadable blue arrows, so I really want the note option to minimize that. I tried NOTE again but then the deep blue arrows are simply impossible to read (to the point I almost failed a lv13 just by that and the most recent mystery is how did I passed 18s like Glitch Angel with that). RAINBOW is acceptable but the occasional purple-ish blue notes are still mildly annoying, and VIVID is similar. I will settle with FLAT for now, something I never would have imagined in the past.
To test if it worked I tried Fascination Eternal Love Mix ESP at 1.0x BOOST, which is BPM400 BOOST:
This is not too bad -- on a mild/bad/tiring day I might get similar result on a proper white cab. BPM400 boost is manageable with 1/1 notes at the beginning, but the double steps in the middle starts becoming hard and the last section is very hard to read given the speed and note option. The song is a clear indication the what works and what doesn't. The only thing yet to be verified is whether or not I played perditus†paradisus too nervously that I treated it more like BPM190 and hit notes too fast. To address that I should think about trying 18s again...
