The geas thing has grown on me. Now Spartans arent just Spartans because of their genetics, theyre Spartans because their genetics are a product of the Librarians millenia long struggle to uphold the Mantle against the Didact and the Flood.

Also, if you want, check this out. Helped me appreciate and understand the geas thing better.
http://www.haloarchive.com/thelibrary/geas

Also, its cool how it explains certain things in The Flood and First Strike now.

"After humans made landfall on Installation 04, geas began activating in humans, notably the Master Chief. The geas would give the humans a sense of familiarity with Forerunner technology. Even indicating certain buttons to press. For the Master Chief, this would continue throughout his journey on Halo.

“The display’s shimmering geometric patterns nagged at him, as if he should recognize them somehow. Even with his enhanced memory, he couldn’t place where he’d seen them before. They just seemed…familiar. … He wasn’t sure why he touched the ‘button’ on the display. He just knew it felt right.”

-Page 95, Chapter 3, Halo: The Flood DE

The ability to detect which button to press on Forerunner hard light panels is a process described as instinctual. On a comparable level to the flight or fight response.

“He seemed to know instinctively how to activate the panel–it almost seemed hard-wired, like his flight or flight response.”

-Page 189, Chapter 6, Halo: The Flood DE

Encountering Forerunner technology on Halo would not be the only catalyst for dormant geas. SPARTAN-II Blue Team’s Fred would encounter a similar familiarity with Forerunner symbols in the Forerunner tunnels under Mechanite Mountain on Reach.

“There was something too fascinating and nearly familiar about those symbols.”

-Page 174, Chapter 15, Halo: First Strike DE"