possibly simpler solution:
hose.mov
the hose is a chain of bones with a Kinematic constraint to follow the nozzle, but they are all also Aim At Constrained to point to the "bottom target" null to make the hose always hang down.
They are also all Aim Roll At constrained to "HoseRollTarget" to keep them from flipping sometimes.
"HoseRollTarget" is constrained to float 50% between the two ends of the hose
you animate the nozzle first, then move the "bottom target" at each keyframe to make the hang of the hose look right. All you animate is those two bones, the rest take care of themselve.
more hose bones and more spline rings would make for a smoother looking hose.
MDL and CHOR you can examine.
hose.zip