From the beginning, I've thought the major element behind the defund Obamacare push was to gain far right Republicans leverage in their fight against the rest of the GOP.
In other words, the far right, going into primary elections, will force certain Republicans to take votes to keep the government open, to increase the debt limit and to "fund" Obamacare. Primaries then roll around and a whole bunch of Republicans who were forced to take difficult votes are now in serious jeapordy.
As proof, John Boehner just promised the House every single thing they could ever want, and it was rejected by the far right. Ted Cruz demanded a bill defunding Obamacare, he got it, and then he filibustered it. The point: continue to corner Republicans until forced to take unfathomabe votes working with Democrats and then run them out of town. The point was not to reach an accomadation or resolution. Not even close. So they will continue to force and corner certain Republicans to raise the debt limit, to pass the CR. Then the rail against these actions for months and months and months as if they were the greatest act of sedition possible. Then they face them in a primary. Basic hardball politics at its core. Except the Democratic Party is not invlolved. It's the GOP civil war and the insurgents are routing the establishment.