I do believe Obama has crossed over the line with his suspensions and delays of legal deadlines which were enacted by Congress. But defining the exact amount of latitude a President should have in these matters is going to be very, very difficult.
Going after Executive Orders and other executive actions is an extremely hazardous gambit. Boehner better think before he leaps and lands on a mine.
His lawsuit needs to be very specific about what actions he has a grievance against, and he best be prepared to provide very specific limitations he expects the Executive to have, because if the court decision comes down in his favor, it will affect the future behavior of every President, and the GOP might just be doing its usual hypocritical whining when their guy wants to do the same things.
A decision in Boehner's favor will certainly embed gridlock even deeper than ever.
I would proceed with extreme caution.