One thing that happened while I was sculpting is the extension on the eye on half of the shark got super skinny, where the other side is like you see in the sculpt.
The only way I found to correct this was to hop into edit mode and symmetrize the geometry, which broke off the eye stalk. Then I had to go back in and fill in the geometry, then finally I could inflate/deflate the geometry again and they matched up.
Is there an easier way to fix things, particularly with find geometry, when things get a little off kilter on half of one's sculpt?
There is a faster tool for solving symmetry wonkiness!
The Symmetrize button used to live in the Dyntopo menu but has since been moved to the drop-down menu beside the X,Y,Z symmetry buttons. If you ignore the location of the button, the explanation here still applies.