Where, exactly, did SE say "Blue Mage parties should contain nothing but Blue Mages"? Back when it was new, I joined FC parties and ran low-level Blue Mages through low-level instances for spells by tanking for them, as well as providing DPS for higher-level instances where both Tanks and Healers were also involved. Moved on to another instance once all the Blue Mages in the party 'got the spell' they wanted.

Resurrections were the least of their worries.