Ok, I understand. You literally mean that both of them will only introduce objectionable policies, not that "less objectionable" might mean, in some cases, "good."
I still don't see the outcome you predict.
TLDR; power consolidation is a risk factor that leads to actual bad policy, not something with actual, palpable negative value in and of itself. E.g. the power of the federal government to end slavery is a win in my book.
* * * *
Let's map "objectionability" onto a number line.
A neutral policy is zero. An objectionable one is on the negative side, a non-objectionable one is on the positive side. The magnitude of the objectionability or virtue yields the magnitude of the number.
I'll go with your presumption that both Clinton and Trump's policies are only found on the negative side of that line. And we'll deal with their policies in aggregate. We'll also assume that current policy is perfectly neutral, at zero:
<---------T-------------C-----0
T = Trump APV (avg policy value)
C = Clinton APV
0 = CPV (current policy value)
Let's map effectiveness to a float between 0 and 1. Simple. If Trump's policies are twice as bad as Clinton's, he has to be half as effective as she for them to equal out. Here's a little table:
APV, Effect, Total value, Who, Worse
-20, .05, -1, Trump, O
-2, .95, -1.9, Clinton, X
-20, .1, -2, Trump, X
-2, .9, -1.8, Clinton, O
-10, .05, -0.5, Trump, O
-2, .95, -1.9, Clinton, X
-10, .2, -2, Trump, X
-2, .8, -1.6, Clinton, O
The problem with that simplification is the assumption that CPV is at neutral, zero. And mapping effectiveness to a scalar factor of APV is also incorrect -- instead, it has to be understood as a normalization factor, attempting to return CPV to APV. The greater the effectiveness, the more quickly CPV achieves APV.
Should any factor bring CPV further negative than Clinton's APV, her effectiveness would become a force that lifts CPV. Meanwhile, Trump's is always attempting to pull CPV further negative towards his abysmal APV.