Hi Jono!
So... you're saying you shoot everything at 5500??
That can't be right... 'cause warm light (evening) will look blue and cool will look warm!
Surely you're click balancing or shooting everything with a CC card (or expodisc, shootsmarter, WhiBal etc...) from wherever the light is coming from.
Albert
In daylight, yes I always use Daylight. And it doesn't make evening light look blue, it makes it look like evening light!
The argument is that in mixed lighting, where you have light and shade, you can't get it 'right' anyway, because there will be a huge difference between the correct white balance in the light and shade areas. What's more to the point is that you don't want it right either! If you do a proper WB in evening light, then you are getting rid of the nature of the light by correcting it.
Of course, you can take an incident reading, but what's that got to do with the price of beans?
I started doing it one day with the D3, I took a walk in the evening with the dog, and checked the white balance frequently, in steady sunlight the camera varied between something like a little under 4000 to a little under 7000 . . . in the same lighting conditions!!!
The two other advantages are:
1. you really learn about the colour response of the camera - it's like using a single film stock for outdoor work - with different speeds of course.
2. if you really need to change the WB in post, then it's easy to do it as a batch.
Truth be told though, using Aperture with the A900 I don't believe I've messed with the white balance for more than a handful of shots since I started using it last October.
Of course, this doesn't relate to shooting indoors, or in mixed artificial and natural lighting.
You should give it a go, it's a real freedom!
I should give credit where it's due, it was Robert here who suggested it last year when I was having dreadful trouble with colour with the D3