Faster Git clones

I arrived at using this plugin when I needed to obtain (and inject builds into) source dependencies from GitHub in a Gradle project. Like others I found that Gradle's built-in source dependencies feature did not support Git authentication, which was a deal-breaker for me.

One problem I have found is that when this plugin clones large Git repositories it takes a very long time. (If you run Gradle using the IntelliJ runner it can also result in an out of memory exception.)

My intuition is that it might be doing a full checkout. This might not be necessary for the plugin to do its thing. Would it be possible to optimise this with something like Git shallow clones to make the cloning step go faster?