The problem with the Summoner is it's a DoT based DPS which means to be effective they have to know the fight better than the White Mage in order to plan out actions before hand which is a massive design flaw for a DPS it guarantees only 2% of the population that mains Summoner will be able to play in very high level raid encounter like Coil or even Alexander because lets face it Alexander is probably going to be a lot more intense and punishing then FCOB. The way other DPS are designed they don't have to deal with knowing every single aspect of the Raid like the Summoner or having to over gear to be accepted into progression groups. The fact that a massive amount of players ran from Summoner and switched to Ninja, Black Mage and Healer should tell SE that the Summoner has a broken design.