Hi,
I've been tracking L2 futures for some time. One thing I noticed is behavior around large orders. If book order is around 2 times bigger than average medium size order, for that time of the day, than it has significant influence on the market. I'll call those orders "bumps", similar to road bumps we have here in London.
It all depends how that big order is "chewed". If market touches that "bump" and "bump" sits there, and quote goes, for example: 40 - 35 - 32 - 28 - 21 - 15 - 7. In other words, if "bump" doesn't budge, but it is steadily "eaten" by the market, than most likely market is going to break out through that level, and it is going to be a big brake out.
If "bump" disappears as soon as it is touched, in other words it was just "bluff", than I haven't observed any influence on market.
For example, few weeks back, there was 305 contracts order on emini Dow Jones on the ask side, around 11:00am London time. I was watching in awe, because at that time of day emini DJ is less than 10 contracts on average, maxing around 40..50. Well, market shot up to that exact level, but order just set there. Market retreated down, and after about half an hour, I guess, every MM in town phoned every other MM in town, and they went second time for that order. That level was broken, in a second attempt, within one minute, and market went up almost 100 points, by the end of the day.
cheers, dejan