I've only be playing Slaughter as healer, first because Flames never have enough heals, and second because otherwise I would go as MNK and I just know I wouldn't last long unless we have a decent among of melee.
As WHM I can obviously see that the lone melee (and tanks) in our party that decide to go attack because he ain't gonna stay behind the whole fight, get targeted and focused first, which is logical, but such an inconvenient.
If you have multiple melee attacking together that would be the idea? but if you're alone then I hope you have heals that can react quickly. Talking of the middle the ADS also seem to hurt melee a lot? which make things even worse. Like with the other FL, if you try to beat the mob you're just offering yourself to mage and their LB.