I have turned off Navbar. For a long time, I preferred to have it on my blog because it provides a search box and simple sharing method. However, I finally realized it costs 2.1 seconds of loading time.

But the story started with the Next blog link, which always redirects to one blog about Pentadactyl, it's obvious to me that there was something wrong with Blogger. I found some discussions about the issue:
http://productforums.google.com/d/topic/blogger/yurRm7gOiMo/discussion
http://productforums.google.com/d/topic/blogger/hq7dcykLLOc/discussion
http://productforums.google.com/d/topic/blogger/MnCkBCXlXYk/discussion
http://productforums.google.com/d/topic/blogger/6G-D9g8kpGA/discussion
http://productforums.google.com/d/topic/blogger/bnwvUVIvkNs/discussion
http://productforums.google.com/d/topic/blogger/z97M2nAIycc/discussion
http://productforums.google.com/d/topic/blogger/XnEUJ48aIAg/discussion
I'd thought about posting a new thread, but then I saw the loading time, the issue didn't matter anymore.

I used this post and FireBug to time the loading. Before, it's ~4 seconds. If I turned off Navbar, it's ~1.9 seconds, that's 2.1 seconds difference. If I only blocked the Google+ share button (the plusone.google.com domain), it's ~2.9 seconds.

The number speaks it all and made the decision for me already: get rid of that now!

What functionality would be missing? Well, basically nothing. I have a more powerful search page and more options for sharing, which already accessible from top navigation menu. If I have to list, then the Blogger brand icon and Report Abuse are the only two missing.

2 seconds page loading time for very simple post on my years old computer, not many blogs can give you that. I don't like fancy or over-stuffed blogs, so that's the way my blog should be.

Think about it: 2.1 seconds, round it down to 2 seconds and only take 10% of it, 0.2 seconds, which is overly underestimated, even for recently built computer I believed. Anyway, 0.2 * 22,100 pageviews (current last 30-day pageviews in Blogger Stats), that would be 4,420 seconds ~= 1 hour, 13 minutes, and 40 seconds. That's the energy I save for Earth.