Soran and the Lursa sisters implanted something in Geordi's visor and used it as a spy cam as he was walking around the ship, ultimately leading to them finding a way to break the Ent-D's defenses and destroy the ship. If the crew had figured out that LaForge's visor was the security "mole", do you think Geordi would feel a sense of guilt - after all, he spent almost a decade keeping the ship together through crisis after crisis, only to see himself turned into an unknowing agent in its destruction. Frankly, I'm surprised Riker put him back on duty so soon after he was kidnapped and tortured by Soran. Considering the fact that the last time LaForge was kidnapped and tortured by enemy agents he almost assassinated a Klingon governor (TNG episode: "The Mind's Eye"), I would have had LaForge go through a ton of counselling and psych evaluations before returning him to duty - he's been through this horrible ordeal TWICE! I also would have had engineers going through his visor with a fine tooth comb to see if it had been tampered with before letting it into areas of his security clearance and sensitivity - never made sense to me.