I know this article is quite old by now, but I must say that this article doesn't make any sense.

I've been hosting my WordPress sites (which is all I use at this point) on 1and1 for nearly two years now and have had full access to every element in WordPress (I use every elements of WordPress in various ways simply to see how they work and can be used). It sounds to me like the installation is set to 1and1's "Safe Mode", which makes it difficult for an inexperienced user to break the installation.

For this, when installing, you're supposed to select "Free Mode" and you will have full accessibility.

My comment is in regards to the "ClickAndBuild" function that 1and1 provides. I've just come across this article over and over, and so here's my input for what it's worth.