Yup, I use AWB because I still face this hit-or-miss white balance. To prevent my "white" from varying, i'll usually try to use one of the preset modes, and skip using a white card to set Custom WB. where got time in sports, with all the action?
regarding the nikon part, that question beats me too. however, Watcher did demonstrate to me when we met up in Starbucks, while chatting over the WB modes, the +/- 3 adjustments. that's where i learnt the extra flexibility of the nikon system
by the way, Zerstorer, does Color Balance in PS work on the principle of Complementary Colours, and Colour Wheel?