Goldfinger,
Correct, of course. But there hasn't really been an application of fusion that's practical for *anything,* so far. Between the article and my conclusion is the surmise that, once invented, it would quickly increase in efficiency, like other similar sources; but could go either way, as you point out.
Fusion uses a fuel almost as cheap and plentiful as dirt (relative to other sources, anyway), and could probably be made free of significant waste. One hopes that, once the process was controlled, these benefits could be realized.