Anyone who saw Duncan play knew he could drop 30, 40 or even 50 on anyone between 1999 and 2004. But that's not how the Spurs play, Pop wanted him to move the ball and share the field goal attempts. In the end, the Spurs won more than the Rockets.
Hakeem was in his prime during his two championship runs. Great runs, but Duncan is also considered to be better than Malone, Barkley, Ewing and Robinson.
While they didn't guard one another very often, Duncan played better than Shaq various times in the playoffs (sometimes Shaq played better too). Now, Duncan always faced Shaq in his prime.
Hakeem played against Shaq when he was 22 and had dismal 1 point per shot efficiency while Shaq scored in similar numbers in far less FGA's.
Prime Shaq, prime Kobe and Phil Jackson was better than anything Hakeem ever faced, and Duncan was too the only all-star of the 02/03 team.