[O] [new exporter] latex: why does {{}} become \{\{\}\} ?

[Myles English]

Hi,

Org-mode version 7.9.2 (release_7.9.2-441-gf287ab @ 
/home/myles/.emacs.d/plugins/org-mode/lisp/)

Can anyone tell me please why (in the examples below) {} exports fine
but {{}} exports as \{\{\}\} ?  Am I meant to wrap these in
#+begin_latex blocks?

In my .org file:

\tikzset{help lines/.style=very thin}
\tikzset{help grid/.style={help lines,color=blue!50}}

In the resulting .tex file

\tikzset{help lines/.style=very thin}
\tikzset\{help grid/.style=\{help lines,color=blue!50\}\}

Thanks,

Myles