Dyson tests--funny that they did not say handwashing beat agitator washing. Giving agitators their due, the fins on most agitators force powerful water currents through fabrics.
Mickey, I don't remember a sleeve type filter except for the red one that slid down on the Hotpoint agitator. Whirlpool had a lint filter to "update" wringer and automatic washers made before the recirculating filters were introduced. The filter pan was pushed down on the agitator, had a double wall design and scoops that worked with the agitator strokes to force water up into the filter pan. Other automatics used something similar for awhile, IIRC. Do you have any idea of the age of the Norge? That knurled brass nut on top of the agitator was probably at one time in the cap of the agitator. The rough surface would have given the nut a better lock into the Bakelite. I know nothing about the slits in the agitator shaft. When you take that agitator out, does the metal inside come out with the agitator? If it does not, I don't see how the brass nut would hold the agitator in place. If the metal is the drive block for the agitator, and the agitator is hollow to allow it to slide down onto the block, then the cap would have held the agitator down on the block and the hose clamps would not have been needed. Sorry if this is way the hell and gone wrong, but looking at the photographs of the agitator without closer examination, I am not sure what I am seeing. Is there a "shoulder" at the location of the first hose clamp? It could be that the agitator was made to accommodate a scoop up type lint filter that would be held in place by the agitator cap and be supported by the shoulder, but that is a wild shot, too. Tom