Putting your demands on the table at the last minute is traditionally a successful negotiating strategy. It's at the last minute that people are focused, that the stakes are higher and that you're the most likely to extract concessions.
I've never been a fan of "brinksmanship." Why waste all that time posturing and misdirecting and as Seth says, "punishing the other party."
I often engage in what I call reverse negotiation. I put my most generous offer on the table up front. Why not? We haven't had to invest a lot of time, effort or energy in fruitless negotiation yet. But as the negotiations needlessly drag on, unless there is a VERY compelling reason to do otherwise, my offers actually get let generous. Eventually, people catch on . . they'd better settle quick before I become totally unreasonable!