It really bugs me that the Blues can't do anything without a GL there. The reasoning is silly--pure willpower is as useless as pure hope, what both need are action, and that's what the rings are for.
Also it means that "And after my schooling in the ways of the ring, will you allow me to return home? To save those I can from the oppression of Evil Star?" is a recipe for disappointment. "Lesson 1: How to mooch off Green Lanterns"
So I do kinda hope the Blue Lanterns are all "Psych! We just said that to try to get Hal Jordan on our side! Taste cerulean justice, interlopers!"