Well I might be outdated on individual match ups since I've been out of the scene for a while. Yet, I will say this:
First we assume that both the player and his or her opponent are using their characters to their full potential. After this assumption has been made we can say that any character that can approach, or harass Luigi safely will have an upper hand regardless of the situation. Luigi's game is more about how the player reacts to the opponent. And while this is true for all characters, Luigi relies on this heavily. Luigi can't just use a move and be safe, these moves have to land or you will be punished. As a Luigi player you want to create the environment you want to fight in. When I play as Luigi I will only approach my opponent to bait a reaction (I won't get close enough to get hit). By identifying these reactions you can start developing patterns and know how to fight that specific opponent.
With that being said, Ice Climbers seem to be a potentially difficult match up for Luigi. They have the tools required to approach Luigi or harass Luigi and still be completely safe. However, if Luigi manages to maintain the Ice Climbers separate, many of the moves that allow the Ice Climbers to be safe are suddenly rendered unsafe. If you miss a move you will be vulnerable. Yet, since a good Ice Climbers player will be able to maintain both units together the matchup heavily favors the IC's. In conclusion, because of these factors I believe that the current -2 rating is completely accurate.
First we assume that both the player and his or her opponent are using their characters to their full potential. After this assumption has been made we can say that any character that can approach, or harass Luigi safely will have an upper hand regardless of the situation. Luigi's game is more about how the player reacts to the opponent. And while this is true for all characters, Luigi relies on this heavily. Luigi can't just use a move and be safe, these moves have to land or you will be punished. As a Luigi player you want to create the environment you want to fight in. When I play as Luigi I will only approach my opponent to bait a reaction (I won't get close enough to get hit). By identifying these reactions you can start developing patterns and know how to fight that specific opponent.
With that being said, Ice Climbers seem to be a potentially difficult match up for Luigi. They have the tools required to approach Luigi or harass Luigi and still be completely safe. However, if Luigi manages to maintain the Ice Climbers separate, many of the moves that allow the Ice Climbers to be safe are suddenly rendered unsafe. If you miss a move you will be vulnerable. Yet, since a good Ice Climbers player will be able to maintain both units together the matchup heavily favors the IC's. In conclusion, because of these factors I believe that the current -2 rating is completely accurate.
and luigi getting pushed on shield by attacks is the PRIMARY weakness to luigi. There must be no way around OH NO
. I also didn't know that Ike jab > everything luigi. 
