y, often times these are fake asks, mms presenting a phoney wall of large numbers of shares. sometimes, the wall will effectively stop a run, if there is not enough momo. mms often work to protect each other if they know that one or more of the mms are in trouble (say, short a stock that moving up).
what you are contemplating is the use of a bit of a contrary indicator. i love watching those mms simply melt away, when i am right! seeing that happen really confirms that volume is pouring into the stock and the mms may have lost control.
still, sometimes the wall will not fall away.
one that i'm trying to do is to stay away from level II until it's time to exit or enter a stock, unless i'm only interested in scalping. that means i trust the chart. that means i use level II only as a way to refine my exit/entry.
mms are incrediblely good at faking the direction of a stock, imo. i have been shaken out many times by the diverse array of tricks and fakes mms throw at traders.