The 3.6.0 feature of dipping only a subset when attempting to dip a large
stack of potions into another potion (other than water) was calculating
the size of the subset poorly. Dipping 9 non-magic potions would always
dip the whole stack, but attempting to dip 10 would split the stack and
dip 2..9, so manually splitting off 9 in advance let the player always
get maximum yield. This anomaly didn't extend to dipping magic potions,
where dipping 2 always dipped "all" 2 and attempting to dip 3..N dipped
2..min(N,9) regardless of N. Also, the decision about whether what you
were dipping was magic was based on the potion being dipped even though
most alchemy formulas yield the same outcome when dipping magic potion
into non-magic or vice versa.
Change the splitting calculation to yield 3..min(N,8) for magic and 7..N
for non-magic, with no extra threshold that can produce anomalies in the
result. Also, the determination of magic vs non-magic is based on the
outcome rather than either of the inputs--unless the outcome is random,
in which case it will be treated as magic if either of the input potions
is magic.