Don't know if you are already in Mt KK...anyway, as mentioned by others, there would be no space for you to mount your tripod at the summit becos it's gonna be over-crowded with ppl. Finding a place to stand also got problem.
Unless, you have booked 2 nights at the Laban Rata guesthouse, which means you will not be in a hurry to get down after reaching the summit. Most groups only book 1 night, so immediately after sunrise and all the photo-taking, they will rush down.
After everybody is gone, normally at abt 8+......you will have the entire summit to yourself and your group. Then, it makes more sense to bring along a tripod becos now you could utilise it if you want.
Hope this helps....