I may be able to answer that one. People who train to sights tend to use them in an emergency.
Train the way you fight, fight the way you train. Yeah, I believe that is true. Using sights in an emergency (fire/return fire) slows you down.
Think, point, click - scan for other threats. Yeah, I know that's true. In an emergency you fall back on how you train. Do you train to "point and shoot"? I do. My last magazine as I leave the range is a point and shoot at an urban combat distance (you mileage may vary). You have to keep you skills up. I am a bit persistent with this kind of CQB training. I live in an urban environment now so I train for it. Something I do when I train for this is to attach a line level to my carry weapon. I tack it right up there on the slide with a gob of that clear tape. It cleans off. I wear a holster on my right side so I take my SAFED pistol w/level attached and go from right hand low to a snap fire position. I do this over and over as I walk thru my house with my little dogs. This gives me muscle memory to repeatedly draw my weapon and return to a level, consistent firing position. When I "point and shoot, I want to point and shoot at the same spot over and over. Thats just me. I have a lot of free time on my hands.
On those sights. Sights are handy when you have the time and cover to aim. I like sights. About those nite sights tho. Now this is my personal opinion, gleaned from those many moments out in the bush, making every mistake in the book. So you take it with a grain of salt. eh mate? If there is not enough light to see your sites, you can't see the bloody target, and if you have enough light to see the target, you don't need the bloody nite sites. They do look tacticool tho.
For those of you who are living in the City, these sights may help in your endeavors.