It's basically a different game. If playing some Street Fighter from time to time won't make you develop bad Smash habits, then neither will playing Smash the party game.
Yeah, I concur with this. While the most fundamental skills and techniques (such as short hopping, teching, recovering, etc.) are equally applicable to "competitive"
Smash (1v1/2v2, stock only, no items, no hazards, tightly constrained stage layouts) and "casual"
Smash (free-for-all, any mode, items on, hazards on, any stage), due to both being fundamentally the same game, the differences in the settings mean that success hinges on
wildly different skills and tactics. Competitive
Smash hinges on watching, predicting, and outplaying your opponent, surpassing mere reaction in order to respond to what the opponent is
about to do rather than what they’re currently doing; however, mindgames are much less practical in casual
Smash due to substantially more stuff going on at any given time, so you have to watch everything on the screen at once and rapidly react to adapt to whatever is currently happening to come out on top.