Half the stuff folks put out there about MMs is garbage. If you trade in 2 or more accounts, which trade through different MMs. You can often watch them move up or down on L2 in conjuction with your own bid/ask.
Many times traders throw small sells out, and they are waiting on bid just below their little whacks, to grab larger buys from the folks they just scared to sell. Much of the time it isn't "MMs trying to steal shares".
A thin ask usually means people just don't have sell orders in, or, for example, there can be 5-10 traders, all using Scottrade(NITE), with sell orders in. NITE only shows the lowest, and with each sell he moves up to the next.
Much of the MM talk is urban legend.
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