seems that since I was last hear a year or so ago, this issue still hasn't quite been cleared up in any FAQ or guide
I did a search, and I came across the only single hit I could find, being thundercould82's post
GD-resist tells you how fast your reyvateil's MP drains when she's singing. The higher the GD-resist percentage, the lower the MP usage. When the GD-resist reaches 100%, MP consumption is halved. You can see how much MP each song uses by checking the Song Magic menu.
The Burst Variation graph shows how fast the songs charge up at each level. Each virtical line represents a level, up to a max of 4 on the right side of the graph. The higher the line is on the graph, the faster the song will charge up at that level.
The C--H harmonics bar indicates how fast the reyvateil's harmonic bar (the thick bar on the right side of the harmonics gauge on the battle screen) fills up. The faster the oscillation, the faster the bar fills.
so I understand what GD-resist is, and what C-H harmonics are, but I still have no idea what the burst variation window is
does it refer to the current harmonics level noted by the diamonds at the bottom
or the level of the song? ie, first vertical line = speed up to lvl 1 4th vertical line, speed up to level 4 4th vertical line to right side of chart = speed after reaching final level of song
that's interesting... did anyone actually prove this? or is it just a theory?
from what I vaguely recall, I was one of the people trying to figure it out, and when I compared Lilim songs lvl 1 to Lilim songs lvl 4, I couldn't find any difference in song speed (and the Lilim costume from what I recall (don't have it again yet, as I'm doing another playthrough now) had two extremes in terms of song speed)
so assuming this is right, then Lilim is essentially saying "really slow charge speed up till lvl 4, then insanely fast"?
that's definitely something worth looking into, but also something that's going to be really hard to check
off the top of my head, I suppose getting a costume which has the lowest end curve, and the highest (again, probably Aurica and Lilim vs something else she has), charging to past lvl 4 at some defined percentage, then checking the damage vs the same enemy type
Going back to the earlier point. I wonder if it may have something to do with how much boost you get. I noticed early game that when the harmanics bar filled at the begining of the game i'd only get a 160% boost to charge compared to the 200 I get now... and maybe thats like the max boost a bar is plus 100%
I think I hit head on. It was a simple test. Took child Misha's standered outfit and aactivated first bar fill up, witch was 140% and compared to her last outfit elfir and got the full 200%. I think this kinda proves burst vareation does effect charge speed but I could be wrong