It's a double edged sword. Sometimes market orders will get absorbed and price will reverse. Other times market orders will eat the available limit orders and price with breakdown even further.
Absolutely true on the ES as well. Actually I meant to mention it when I was writing the earlier post, but forgot when I was done rambling If you see 4500 orders stacked at a price on ES, you could definitely get away with placing a trade in the direction of that price point.