You have a D3 and a great selection of lenses, so presumably there are many gyms in which you would not need to use strobes. Did this gym have a poor lighting system in spite of having white walls and white ceiling?
Whether to use strobes depends in part on the desired end result. The image quality of a shot at ISO 400 (which I typically use when strobing) on a D3 is still superior to the quality of the ISO 4000-5000 shot that would be required for the typical HS gym, including this one. You may not notice it so much in an image posted on the web or in a 4x6 print, but blow that image up to 16x20 or so and the difference is readily apparent.
The strobes provide a couple of other advantages, too. First, the color rendition is better because the spectrum of light from a strobe's flash tube is "whiter" than even a "white" fluorescent. (Much less the fluorescent bulbs in some gyms!) And when shooting down-court, the foreground (player) is closer to the light source than the background walls. The fall-off of the light on the distant background causes it to be darker than the foreground, so the subject pops out of the background nicely. This isn't true of all shots; it depends on the angle and location of the lights and background. You can see the effect in shot #3, for example, but not so much in shot #1 where the wall is close to the corner where one of the strobes is located.
If I'm shooting for a client who doesn't need maximal quality (such as the studio that does photos for the school's yearbook), I'll skip the strobes and shoot with high ISO. Those shots are more than adequate for reproduction in the books. I'll also often shoot without strobes if I'm doing it just for fun since it's easier.
The main site where I sell these images requires that basketball be strobed, so I don't really have a choice when shooting for them. But I also like the results I get using strobes.
Okay Jon. These look great. You need to spill it all.... if you are shooting at ISO 400, 1/250, and f4, how many stops under ambient are you and what is the power setting on your speedlights? I shot in a middle school gym last week at 1/200, f3.2, and ISO 1000 to 1250 to get two stops under. The flash was set at 1/4 power, on camera, bounced off the ceiling. I have everything I need to set up two strobes, but I don't know if they will let me, and from the behavior of some of the kids that were in attendance, I don't know if I want to. I am insured, but I just don't know if it will be worth the hassle.
It's funny you say that, Steve. Just tonight I was in a gym where I was using speedlights.
This gym has some puky ochre colored walls and ceiling. (And the paint is peeling off the ceiling, leaving big brown splotches.) Plus, the court is far from the end of the gym at one end -- and the cheerleaders occupy the other end. So, bouncing strobes didn't seem like a great choice. I opted for direct lighting instead, cross-lighting the end of the court with a pair of SB-800's. Last year and the year before I would have used the AB800's for that, but the advent of RF wireless TTL via Pocketwizard ControlTL radios makes Speedlights a better choice now, I think.