The target attribute is a misfeature of HTML anyway. All it does is make it unpredictable what happens when you click a link.
It was in part to mirror the MDI "window in a window" concept. MDI is useful for "productivity" applications, but maybe not so much for web browsers. What's good for the goose is not always good for the gander. I think we need a new standard for "productivity" applications (office/CRUD/desktop). Bending the Web that way has made a big friggen mess.
Seems more like you're blaming HTML for a programmer's poor webapp design. There are lots of other ways to make a link click unpredictable, and lots of reasons an app wouldn't want to rely purely on the default behavior.
What web app design? Writing an HTML document does not make one a programmer.