The Magic use 92.6 possessions per game. Boston uses 91. Is the difference really that big? The Lakers are more of an up-tempo team, they play 95 possessions per game. True run'n'gun teams, like the Warriors and the Knicks, use +97 poss per game.
Play-offs games are slower, but teams can be successful playing faster. But Orlando is more a middle-of-the-pack team in terms of pace. Even though up-tempo teams can have troubles executing half-court sets, I really don't think that's the case with Orlando. They're pretty comfortable playing a more grind-out game and they have a diversified game.
Manu missed around 15 games in the last 2 seasons. Parker has missed, I don't know... 3 or 4 games per year on average since joining the league? Duncan, I can't even remember the last time he missed a game because of an injury. 4 or 5 years ago? They're old, but they've been healthy; and their big 3 is younger than ours. Mason and Hill insulated some youth in their supporting cast.
YOu're right about Houston, their best players are very injury prone. But if they're healthy at the same time for a 2 months period - and it has happened before - they have a chance to compete for the title.
I personally have never seen the grind it out side of the Magic. Maybe its there, I don't know.
I'm not totally sure the numbers you reported about the Spurs are accurate. I would believe you if I saw the injury data from a primary source. TP if you can find that.
But still, assuming that your numbers are accurate, I don't think that data takes the whole scope of things into account. Manu was playing all throughout the playoffs, but his ankle was really messed up. He really struggled out on the court with his injury, and that hurt the spurs a lot. Just looking at the raw number of games missed isn't really enough, because players do play through injuries, and those injuries often make them much less effective.
Their big 3 is younger than ours, but their whole team is older on average. Also, Manu has a lot of miles on him due to the way he plays. Parker has also been in the league a long time, since he was drafted at age 18. He's what, 26 or 27 now? That's 8 or nine years pro.