An iron-clad law of politics is that whatever dirty tricks you use today will be used against you tomorrow.
According to the Constitution, there are several offices that require Senate approval of Presidential appointees. When the Constitution was written, it was assumed that Congress would be in recess for months at a time and that it would take days or weeks to unexpectedly reassemble. That was reasonable when messages had to be carried by someone on horseback. This created a conflict between the need to fill offices and the difficulty of assembling Congress during a recess. This was bridged through recess appointments. The President can appoint someone for a year allowing plenty of time for a formal confirmation the next time Congress is in session.
For the last century presidents have used recess appointments as a way of getting controversial appointees into office without a Senate approval. A few years ago the Democrats decided to stop the Bush administration from making recess appointments. They did this by never going into recess. During periods of traditional recess, a few senators would stay behind and hold pro-forma sessions in which the only business conducted was a motion to adjourn. Note that the Democrats supported this including Senator Obama.
The Republicans followed this precedent and left the Senate in session at the end of the year. They could do this because each house has to have the assent of the other house in order to declare a recess so the Republican-controlled House could keep the Democratic-controlled Senate in session.
But, when President Obama returned from Vacation he declared that the Senate was in recess and made the appointments anyway.
The dirty tricks are piling on each other. First there was the misuse of recess appointments, then pro-forma sessions, and now a President ignoring the Constitutional definition of a recess and declaring one on his own. This last one was particularly odious because it tromps all over the separation of powers. If allowed to stand then this could mean the end of Senate approval. You know that this will come back to haunt both parties.
This is also one of the worst examples of an imperial presidency imaginable. And it came from a former professor of Constitutional law.