Maincoonmaniac - Mysteries of the Vortex was the article I was referring to. I only have the original magazines (from 1996) and wasn't sure they would be available online but you've got links to it now from several others above.

It is an interesting read highlighting the key variables I mentioned earlier.

To be honest, I think it would be hard to beat the Ilford method you seem to already be using, but with manual shuffling/agitation in trays with fills/dumps or a siphon rather than in an archival washer.

Also do not neglect temperature. Room temp water will wash more efficiently than cold water, although the hypo clearing agent mitigates this somewhat.