Yes, MMS plans can come to fruition if those feint of heart sell into their games. They can actually "push" a stock down by undercutting the last PPS on the ask side. The way to fight this is to continually buy whatever they throw up on the ask instead of, what many weak handed individuals do and panic sell at the bid. Eventually, they have to let it go. In the same breath, it may not be a MM that is creating havoc to short cover. It could very possibly be weak handed individuals trying to squeak out a few more dollars on the ask which is below the last PPS. Just games....exciting ones at that.