https://www.youtube.com/watch?v=evxlR5ILiEgI asked about it some time ago and got no answer and I don't think there's any info about it in the manual, so I'll leave it here for other people.
I have to do that process because my MiniBrute that I didn't use in a long time is severely out of tune (If C3 is tuned, C4 is fine, but I get C5 at +15 cent, C2 at -15 cent and C1 at -30 cent). I haven't finish yet, I hope I won't get electrocuted (so easy to miss the tuning screw... nice job).
After tweaking it for a while, I don't have high hope I'll fix this issue. I'm guessing I shouldn't expect a perfect tuning, but to what point is it acceptable?