When renormalizing "non-renormalizable" operators within an effective field theory (EFT) one usually has to introduce additional (higher-dimensional) operators to the Lagrangian which act as counter-terms.
Using dimensional regularization M. Neubert claims in his lectures that one can generally write the bare operators $\mathcal{O}_i^{(n)}$ at mass dimension $n$ in terms of renormalized operators $\mathcal{O}_j^{(n)}(\mu)$ as
$$\mathcal{O}_i^{(n)}=\sum_j Z_{ij}(\mu)\mathcal{O}_j^{(n)}(\mu)$$
where $Z_{ij}$ are the corresponding renormalization factors. This generally means that the resulting renormalization group equations (RGEs) will mix different operators within certain mass dimension but they will not mix operators of different mass dimensions.
Sadly he does not explain this statement any further. However, I would like to understand where it comes from (it might be that it's some obvious reason which I don't see...)
My question is therefore:
Why does dimensional regularization not lead to mixing between operators of different dimension?
What I tried so far: (This might be irrelevant...)
To solve this I tried to start with a "simple" case:
Let's take the example from pages 389-390 from M. D. Schwartz' "Quantum Field Theory and the Standard Model" of a non-renormalizable scalar $\Phi^4$ theory in $d=4$ dimensions
$$\mathcal{L}=-\frac{1}{2}\Phi(\square+m^2)\Phi+\frac{g}{4!}\Phi^2\square\Phi^2$$
Here $g$ has mass dimension $-2$ and following Schwartz the transition amplitude $2\Phi\rightarrow 2\Phi$ at one loop using cut-off regularization i.e.
$$\int_0^\infty dp\rightarrow\int_0^\Lambda dp$$
is proportional to something like
$$A\sim gp^2 \qquad\qquad\qquad\qquad\qquad\qquad\quad\qquad\qquad\;\,\text{(tree-level contribution)} \\+g^2(C_1\Lambda^4+C_2p^2\Lambda^2+C_3p^4\log(\Lambda)+...)\qquad\text{(1-loop contribution)}$$
where the $...$ denote terms that vanish when taking the limit $\Lambda\rightarrow\infty$. Now, to cancell the divergences that result from the loop contributions one has to introduce additional counterterms to the Lagrangian of the form
$$\lambda \Phi^4$$
which cancels the $\Lambda^4$ divergence and
$$\kappa\Phi^2\square^2\Phi^2$$
which cancels the $\log(\Lambda)$ divergence. Obviously, this would mix operators of different dimensions.
While I don't really see which kind of loop diagram would result in a $p^2$ or $p^0$ dependence (as the $p$ dependence here comes from the vertices and at 1-loop level there will be at least two of them each giving $p^2$), following Schwartz we would still have to add the $\Phi^2\square^2\Phi^2$ term and hence mix operators of dimension 6 and 8.
I don't see how dimensional regularization
$$\int d^dp\rightarrow \mu^{2\epsilon}\int d^{d-2\epsilon}p$$
would change anything here.