The LC and LC+ are quite different animals. The LC stuff draws quite a bit less power, and of course has no couplers. Also, the smoke units have higher resistance in the LC vs. the LC+, so they draw less power as well.
The couplers alone can draw close to an amp when fired. I've noted that many TMCC locomotives won't properly fire the couplers with less than around 15-16 volts on the track, the LC+ couplers are the same design.
With smoke, movement, etc. I can easily see that the couplers would be marginal with a 2A brick.
