I am not necessarily recommending that one should omit the optional tags. However, it is worth noting that the option to do so while conforming to the HTML5 spec is there. The "certain conditions" are not really much to worry about. I think they are drafted quite carefully and are quite sensible. If one is writing simple HTML documents, say, for blog posts, text-based articles, etc. one can safely omit the optional tags without running into issues due to the "certain conditions".