that's actually how I handle many things with my children--group actions and encouraging cooperation
But there are times when I need to give instructions and my children need to do things and I *ask* them to do it only if their compliance is optional. Otherwise I tell them what they need to do. If we are out in public I might say "we need to clean up" but then as we're cleaning I might say, "Dd, you need to grab that there and hand it to me; Ds you need to get that toy and put it in the bag; etc" With my 3yo I make it as fun as possible and encourage him in the ways that he responds to, but I also see this as a time where I'm teaching him what is his responsibility and no one else's--and cleaning up his toys is *his* responsibility. *He* needs to do it. I help, I model, yet I this wording is to teach.
hth