I don't like motion in my pictures, so 1/400th doesn't work for me. I think sometimes we develop our styles around our limitations of gear and conditions over time, so back in the day of the 30D, I couldn't shoot high ISO without huge detriment, and I also tolerated motion blur and not-so-crisp shots, and that became my preferred look in the day.
However as my gear evolved. and lighting at venues improved, my expectations evolved, and now I want everything frozen in air, that is the look I want (and probably did since the beginning), but now my gear allows it. I don't like seeing blurry players, arms and legs, etc.
All personal choices, but if you like the stopped action in air, 1/400th only works at the times where acceleration/momentum have stopped, so at the top of a jump shot, or top of a dunk, etc. But as a player flies through the air horizontally on a fast break, 1/400th simply won't cut it. Shoot, my kids move fast enough to make a blur at 1/400th at home.
But in cases where lighting is so poor, one is left with little choice, either deal with high ISO or have blurred action/players on a majority of photos. 
This is the look I go for, and I often crop as well, which will magnify motion, so it further complicates matters. I even want to see the dimples on the ball.
