*Note: this is more a theoretical question, the actual use case has already been solved upstream.*

Let's assume a class or package defines a latex template with some long and complicate code. A user would like to make some small changes. Do they have to copy the whole template or can they somehow patch an existing template?

Let's take the following simplified example. Can this be patched to have `Quack` left aligned instead of centred?


```
\documentclass{article}

\NewTemplateType{footer}{0}
\DeclareTemplateInterface{footer}{quack}{0}{}
\DeclareTemplateCode{footer}{quack}{0}{}{
  \centering Quack
}
\DeclareInstance{footer}{quack}{quack}{}

\begin{document}

test

\UseInstance{footer}{quack}

\end{document}
```

For beamer templates one can simply patch them with something like

```
\patchcmd\beamer@@tmpl@frametitle{sep=0.3cm}{sep=1cm}{}{}
```

so I'm wondering if something similar is also possible for latex templates?