Yeah, if you're confident with that smash and the opponent can't deal, go for it. It's just not a good habit to get into for when you play better players. Particularly if you're a shorter player like you say in your post, you have even more reason to only smash when you get very close to the net, and to focus your effort on learning how to set your points up to get those winners. My smash isn't great, but it was good enough at the lower levels, so I used it. Now I'm moving into the higher levels at my club, and I am relearning my entire overhead game to get rid of the habit of smashing at the wrong times. Wish I'd had the discipline to not get myself into that habit in the first place :p