It's really an immutable law.
Drawing lines on a pumpkin doesn't make it a watermelon.
To put it more simply,
it's often divided into
appearance tiers.
Even if ㅆㅎㅌㅊ gets plastic surgery and becomes a big hit, it's hard to get by with ㅍㅌㅊ. ㅆㅎㅌㅊ is a ㅅㅌㅊ, and
even if a ㅍㅎㅌㅊ gets plastic surgery and becomes a big hit, it does not mean that a ㅍㅌㅊ~ㅍㅅㅌㅊ
can run two sections only if it really hits the jackpot in its appearance tier. Otherwise, there are cases where it can run for one section or even not run at all.