The AMP machines had a hollow agitator that could not be used for detergent dispensing. The original lint filter agitators had a pumping chamber between the upper skirt with the fins and the skirt underneath that. If you knew what to look for, you could have seen it in a POD this week in the photograph of the underside of the agitator. When you poured the detergent into that chamber, it did not just empty out onto the upper surface of the agitator skirt by the fins, but was held, to a certain extent, in the chamber until it was flushed out by the pumping action when agitation started. Unlike the way the water exits the lint filter in the Power Fin agitators at the base of the column, water exited the original Lint Filter agitator just under the edge of the skirt. This was the construction for all of the Bakelite Lint Filter Agitators as well as the first turquoise agitators. Once they got rid of the pumping chamber, it made no sense to go the extra step of pouring the detergent into the agitator since it would just fall out on the skirt, the same as if you poured it around the agitator column.