Blogging forces some unique constraints upon the author, these are mostly societal and expectations, not technical. The blogger is expected to write a short essay (french for "to try") on a regular basis. This stream of text is also expected to stay on a single topic, the best to feed the point and click sensibilities of the larged audience possible.
Blogging is broken. Here's why.
The short form doesn't allow for the necessary amount of exposition necessary to lay the groundwork for common understanding that is necessary to overcome the limitations of text and the vagaries of human language. There are always differences between the intended meanings of the author, and those inferred upon reading. It's necessary to supply more than one set of explanation to help the reader decide which of their multiple guesses at the intent of the author is closest.
Conversation involves listening to the other partner, and giving feedback on the concepts discussed, to make sure your minds are as close to synchronized as possible. This helps then ensure clear communication of the intented subjects. The better the communication, the further the reach from the everyday is possible.
In order to be able to discuss deep subjects, specific vocabularies must be developed... specific metaphors, and examples. This is the reason doctors have their own medical speak, and programmers know what loops are.
The short form doesn't allow this exposition at length. It forces an artificial division of text... which reduces the amount of signal, and increases the proportion of text used to frame each piece... thus it's not best for very deep subjects.
The limits of what you can express and explain are the very limits of your ability to change the world. If nobody was able to explain the chain reaction, the atom bomb would have never made it out of the theory of one physicic and into reality.
Language is power.
Blogging can be tweeked, ever so slightly, to be more powerful. The limitations are not technical, they are societal, so we don't even need new tools... just new expectations. Fortunately, expectations can be adjusted as a matter of intent.
Blogging tools allow keywords on pieces of exposition, to link things together. Blogging tools allow the linking of a longer explaination seemlessly into your text, to help shorted the text for the reader already in sync, while providing additional support for the reader who is not familiar with the topic, or has additional doubt about the intent of the author.
The need to stay on a single topic is an artifact of the pre-tagging days of blogging, and is hereby declared obsolete! (HA)
Actually, if you give up the idea of having a stream of regular readers, and rather chance meetings of other minds, your point of view is shifted... and your emphasis should then be on allowing the best (easiest) discovery of the content you already have. Linking back to previous work related is one of the most powerful tools to accomplish this. The calendar based archive is appropriate for a single-topic blog, but the entire creative output of a person will necessitate new and better approaches.
Suggestions for improving blogging in general.
Don't waste time and emotional energy limiting yourself to a single topic, issue, etc... go ahead and enjoy the freedom of free association, but please be sure to tag things, and nuture your own links, and links to others.
Revisit your older work, update, revise, correct it... much as if you were to produce a new edition of a book... if you expect people to read it, you should be willing to take the effort to fix mistakes that you've found, and to clarify it. Mark your changes to help avoid confusion if they are significant.
Give up the idea of having to do something every day... just spend time on it when you like. If you need to peek at your Google analytics, go ahead... but it's like dieting, there are ups and downs, and you have to keep focused on the big picture and not the numbers immediately in front of you.
Tag everything, prune the tags (get rid of tags only used once that you doubt you'll use again) to make your index smaller.
Ask others for feedback... give others feedback. It's lonely here out on the small end of the long tail. Your time and attention is the most valuable thing you have to give. A little bit goes a long way.
In summary... blogging daily on a single topic is broken... blogging at length with good links back to relevant topics and a good index is better.
It's the same tool set, you just use it a bit better. You extend the reach of topics you can discusss, and thus extend the extent to which you can change the world.
Which is what we all want in the end... to leave it better than we found it.