I would have thought it depends on what the subject is. With a shot of a bird that is highly likely to fly away any moment you don't have a lot of choice but to point and shoot hoping to get it somewhere in the frame :). That said I would try to set as many things on my camera ready for that type of shot eg aperture /iso . if I knew I was looking for it. If I had more time with less flighty subjects then I would try adjusting pov if possible to get a better shot. eg uncluttered background, etc. With landscape or things that are not going to run or fly away - yes I do consider the composition and try to get something like what I want or imagine the finished image to be. eg look to include a foreground, etc. (Not always sucessfully of course.) My experience is that it is a bit like driving a car at first there are so many things to take into consideration -change gear, brake, signal, manouvre, mind that old lady, etc. that it seems to be impossible to consider all those things before getting to the point where you press the button. But it comes, and the more I practise, and see the results, the more I find that next time I am faced with a similar situation I am considering more things before pressing the button. But with me it has been a process of learning - what was once: unconciously - unable, changes to conciously - unable, to conciously - able and hopefully one day to unconciously - able. When I have reached that stage that I do all the techie bits unconciously - able then I will have more resource to spend on composition. I do think it can be overdone too though, because you have to remember that something grabbed your attention to take the photo. in the first place, and it is really this attention grabbing element that is so important to a good shot. A brilliantly able, technically perfect picture, could be rather dull if it has no feeling or inspiration behind it.

And every one said, 'If we only live,
We too will go to sea in a Sieve,---
To the hills of the Chankly Bore!'
Far and few, far and few, Are the lands where the Jumblies live;
Their heads are green, and their hands are blue, And they went to sea in a Sieve.

Edward Lear
http://www.nonsenselit.org/Lear/ns/jumblies.html