I have just spent the weekend with my sis and she has 4 children, 2 teenagers and 2 20 somethings and I really value her experience.
I have the same trouble with dd and it drives me to distraction, it really does.
My sis said that us parents now are under a lot of pressure to be nice (not that we don't want to be nice bykwim) and think we should be seen to be giving choices to our children when really, thats not what they need.
She advised me not to ask dd would you like to do this or, can you do this, as her response is always likely to be no, given a choice. So she's told me to just to give her the instruction and not an option to say no.
I have to say, I have done this today.....yes i've been doing it for a long time but it does seem to work.
So, 'dd come and put your shoes on now', rather than, 'dd, please can you come here and put your shoes on now'. I know, the 2nd one is nicer, but the 1st just might get the job done quicker.
It remains to be seen whether I will remember to do it.