You really need to get off of this argument, that the people in the forum represent the majority of Blitz players.
http://yourlogicalfallacyis.com/anecdotal
The forum is a small sample, but is not the entire sample. I've gone over the math before -- it's not even a statistically significant sample.
Say there's now 70 unique posters on this thread, and 100% of them hate the nerf. According to the Rock Band World FB app, the average number of people who have played each of the core Blitz songs is roughly 31,000.
70/31000 = .002. That's 0.2%. Not even 1%.
A vocal minority of 70 people CANNOT be an accurate representation of 31,000... let alone the 207k people who have played Death on Two Legs, or the 219k people who have played These Days.
You want the smallest possible sample? I own a handful of DLC but have exported all the previous RB games. Doing a quick browse, the song with the least amount of unique players is Letterbomb from GD:RB with 1,211 players. 70/1,211 = .058. Congratulations, we are now at 6%! That means 94% of the player base is still unaccounted for!
Only the entire sample can be 100% accurate. You know who has data for the entire sample? Rock Central. And if Rock Central says there weren't a lot of players out there using Flame notes to begin with -- i.e. they preferred using Blast, Runway, or Pinball over Flames -- then nerfing Flames was NEVER a problem for those players. It's that simple.
However, this is NOT to say that there isn't a problem, or that we aren't important to Harmonix. Obviously, HMX is listening to the vocal minority and trying to find some way to placate us while not making all other players angry. For that, I am grateful. It seems like all the reasonable arguments have been posed and are being debated internally.
At this point, we just have to wait.