Just gave this talk at W3Conf about some of the innerworkings of HTML5. Lots of did-you-know and cool insight into how browsers work. 37 minutes long,

The Primitives of the HTML5 Foundation - Slides

I do discuss optional start and end tags as well as not quoting your attributes. I concede that these ideas scare the shit out of people. In fact, when I first heard Jens Meiert propose the idea in 2009 my brain rejected it.

Still, I think many of the markup parsing curiosities that can be frightening only need to be understood by HTML minifiers. Always leave it up to tools to make your frontend payload smaller; you just want the most comfortable and maintainable authoring environment possible.

I shared them in this talk because 1) it can lead to writing more beautiful HTML that is easier to maintain. Leaving off </li>’s is a good example. 2) I just want people to consider browsers less of a black box of uncertainty. There are rules and specs that define behavior, so once understood you can feel confident relying on a consistent behavior. We certainly don’t have that consistency across all the web platform, but for these examples you do.

In summary, I’m not advocating you write more spartan markup if you don’t want to. But if it makes you feel good, by all means, go at it; you know now how the browsers work.

ps. the monkey HTML shirt I wore is from a store in tokyo; solo location. but they also sell on this delightfully overwhelming site