Overwriting Latex image positioning in pandoc generated pdf

Pandoc is a very powerful tool, I'm extensively using it for writing documentation, papers and so on.
You can generate pdf, html, docx and many other formats trough a compilation of markdown source file.

Often I use it to produce nice PDF documents, in this process your Markdown document is parsed and rendered using a Latex template, you can obtain the default template using the command:

pandoc -D latex

Unfortunately all images with a caption tet are rendered in Latex using the htbp floating positioning, this is hardcoded in pandoc.

Markdown code:
![I/O connector](img/1.jpg)

Latex code:

\begin{figure}[htbp]
\centering
\includegraphics{img/1.jpg}
\caption{I/O connector}
\end{figure}

Sometimes the [htbp] positioning doesn't fits my needs and I prefer to use the fixed [H] positioning.
Over the web you can find a lot of solutions suggesting to compile your Markdown in a Latex file, parse the file with sed and then use pdflatex to generate the PDF.

Now, I found a way to overwrite the Latex {figure} environment directly into the Latex template:

% Overwrite \begin{figure}[htbp] with \begin{figure}[H]
\usepackage{float}
\let\origfigure=\figure
\let\endorigfigure=\endfigure
\renewenvironment{figure}[1][]{%
   \origfigure[H]
}{%
   \endorigfigure
}