Just twist and pull up on the elbow piece that's connected to the vac. To unblock the hose I run water through it. No need to to take off the fittings.
I blocked a hose right it the middle a little while back and could not for the life of me unblock it. Ended up cutting it down and usin it as a short hose for my mitresaw.
I've never really had a blocked hose, but I never use less than 36mm for cleanup, also I always remove my hoses from the vac and put the suction end into the vac inlet so I'm pulling from the other end when I'm finished.
Agree with [member=25351]rst[/member]. Whenever I have had a blockage, usually when using it on the OF2200, I just reverse the hose and it clears itself (eventually).