The traditional approach is going to be faster because the browser only has to download, interpret and display. The approach you're suggesting would cause the browser to have to download, interpret, change * n times and then display.
That's as far as rendering goes.
As far as maintainability goes, you're creating a nightmare. That's the key to development. The number of nightmares in maintainability is proportional to the "quality" of the code, IMHO. Performance and optimization should come second to maintainability. (There are exceptions, of course. Nothing is black-and-white).
HTML was created to be an expressive language. Javascript wasn't. End of story, in my opinion.