With all the changes to Blogger's template system, it seems no wonder that my original tutorial for hiding the Blogger nav-bar no longer works effectively (particularly for newer template designs).
Hide the Blogger nav-bar in a few simple steps:
1. Go to Design>Edit HTML in your Blogger dashboard
2. Using your browser's search function, locate the closing tag in your template's HTML markup.
3. Immediately before this line, paste the following section of code: navbar {blah;}
4. Preview the changes to ensure everything looks the way it should, then click "Save".
That's all there is to it!
Is it okay to hide the Blogger Nav-Bar?
However, I must point out that in hiding the nav-bar, you will lose access to some functions from within your site, such as the ability to access admin-pages and the random "Next Blog" links.
Don't forget that you could choose to alter the nav-bar colour and transparency through the Design>Page Elements section of your dashboard if you'd prefer not to hide it altogether!