Your link gives me an access denied page. Even if you are correct about the trend of events, this time we have to consider a relatively big incentive facing Obama, namely his legacy. I believe it to be a relatively big incentive because I don't think he wants to go down as the first black president in history without having done something of significant proportion. We also have the 2016 elections right around the corner. This time, it is well known that the minority vote (including those of Latinos) do in fact have a decisive effect on the election results. I think that that will serve as an incentive for democrats to lend their support on immigration if they want to keep the presidency. These are just two new factors that one needs to consider when looking at changes in the trend of events.

One must also keep in mind that the EO doesn't fit the trend that you point out, just as DACA didn't fit that trend.