Is there any way to remove a search bar?

[nrwinner]

I want to conditionally show a search bar in the header - show if there's content to search, hide otherwise. With other header options I would simply use setOptions and set them to null or undefined but that approach doesn't seem to be working. Interestingly enough, I can add a search bar if one did not previously exist, but once it's rendered I can't seem to remove it. Anyone know of a way to do this?