I will allow that one of the poster's has the world's best behaved 6 year old, only because my 6 year old turned 7 recently

I have three children, 12-9-7, very well behaved, very well mannered, and the boys even like wearing suits (freakish - yes, I know...) All of that said, I think this is a good decision.
Time breaks won't work - as said, what do you do with the people with the 8:30 resv. who come with kids, the cut-off being 9? Just doesn't work.
I would hate, however, to see all fine dining go kid-free, in large part because children have to learn somewhere. If parents really want to teach their children how to behave in a restaurant it will be tough to do in Sci-Fi theater or Whispering Canyon (talk about un-doing some of that work...

). Other thought - allow for lunches with kids - dinners without.
Finally, we all know that life (unfortunately) is filled with rules that are not enforced. I can think of some extreme laws which existed for years 'on the books' where governments are concerned which we would all be thankful are not enforced. It sure would be nice though if management at various places would get a back bone and approach the rowdy tables - tell the family their four year old cannot be in the restaurant in a wet bathing suit or (YUCK - I've seen it) barefoot. Stop children from putting their fingers in buffet food.
And of course there's the always controversial refillable mug rules.
