Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.
sanj....you wrote "either i don't know something or"...could it be that you don't know that one shot is better(sharper)than servo for "non action" shots? I'm sure you know this but I just thought i would point it out just in case. (i'm sure you do know because i've seen your awesome images)
the main reason for wanting the set up steve describes is to quickly and more easily switch from servo to one shot by having the buttons right next to each other. ("af-on button" and "*" button) (servo and one shot)