An oracle with the Lore mystery can pick the Whirlwind Lesson revelation:
Whirlwind Lesson (Ex): You can quickly browse through a magical tome or manual, gaining its benefits with only a single 8-hour study session (rather than the usual 48 hours over a period of 6 days). At 7th level, you may allow another character to join in your study; both of you gain the full benefit of having read the book. At 15th level, you may share your whirlwind lesson with a number of characters equal to your oracle level. The benefits to you are permanent, whereas your students gain the tome or manual’s benefits for a number of days equal to your Charisma modifier but then forget what they have learned.
It is explicit that when shared with a group of people (the 15th level ability), the benefits are temporary. But what about the 7th level ability, when sharing the full benefit with one other character?
I am confused by the last sentence ("The benefits to you..."). Which benefits, specifically? Maybe it only refers to the 15th level ability, however maybe it instead applies to both the 7th and 15th level abilities. I suspect that the pluralization of "students" implies only the 15th level ability, but I want to be certain. But if it applies to both, then that would mean that the 7th level ability (i.e., benefits to one other character) is also temporary.
Does the other character permanently gain the benefit, or just temporarily?