AST and SCH tool kits don't require you to be in melee range for any skills beyond auto-attack, which is a pathetically small boost in damage in the vast majority of content. I am not in the Raid scene, so I can't speak for the specific mechanics of such fights.

So, I was wrong in 0 benefit, but the arguments giving are so painfully situational that it feels like a bad habit to get into. A healer should place themselves in the center of the party.

White Mage is the one healer I haven't taken to 60 yet, so I don't have practice on Assize.

Also, if a ranger is out of Medica/Succor/Helios range, there is a good chance they aren't taking constant damage from an attack save for a raid wide impact. IF THAT IS THE CASE, then said ranger should be informed to move in for the AOE heals required. That's only one step up from not standing in stupid, and if that's too hard then keeping you alive is a waste of MP.