Apollo 17 would break several crewed spaceflight records: 1) longest moon mission duration: 12 days 13 hours 52 minutes (just a day and a third shorter than the 14 days set in 1965 by Gemini 7), 2) longest total lunar surface extravehicular activities (22 hours 4 minutes), 3) largest lunar sample return (110.52 kilograms or 243.7 pounds), – longest time in lunar orbit (6 days 4 hours), and 4) most lunar orbits (75).
The successful Apollo 7 flight cleared the way for a US moon landing in 1969. Still a lot of flight and ground testing remained and there would probably be surprises. The greatest concern was Nasa had to complete three virtually flawless missions and achieve every major test objective before a lunar landing could be attempted. The odds seemed to be stack against NASA.