In the simplest setting, we have mirror symmetry for $\Coh(\C^* \times \C^2)$.

Next, we are going to take symmetric power.

Do you remember what happens when two eigenvalues collide? No, don't do Hermitian matrices, that will never be nilpotent.

What if you have a matrix that looks like $( (1,1), (0, 1+x) )$. What is the eigenvector for e.v. $1+x$? How about $(1,x)$? Eigenvector for $\lambda = 1$, is $(1,0)$. So you see, when $x \to 0$, the two eigenspaces also collide!