Not really, although it will probably be useful for you to be generally aware of how distributed version control works. The main thing you need to know is that if you want to use the plugin with a given model, you'll need to choose a directory/folder where the local GIT repository will be created and your versioned objects will be saved to.
The simple answer is that it doesn't (not yet anyway). Have a look at the import usage scenario and hopefully you'll understand how the plugin gets around this challenge.
If you are going to have more than one person working on the same model, then the answer is yes because at some point you will want to merge and share the content those people are working on. Even if you have a well partitioned team who don't need to share each others content, you'll probably still want someone who knows about GIT to be the owner of the repository where your models will live, just so they stay organised and in case you do have a situation where you want to share and merge content.