@billstevenson,
Thank-you for the acknowledgement but let us not forget the contribution that @whart (Bill Hart) made in publishing the book and making it available for free through his site The Vinyl Press -.
Otherwise, please remember what the book says in the Forward: All cleaning procedures specified herein are presented as only “a” way to clean a record. No claim is made there is only one way to approach the process. In the final analysis, the best cleaning process is the one that is best for you. All methods/procedures specified here present opportunity for experimenting with different cleaning agents, different cleaning brushes, different drying cloths, and different cleaning equipment.
@faustuss,
If you are curious, here is the patent for LAST - 1499067499117143667-05389281. It’s nothing more than a perfluorinated oil dissolved in a perfluorinated solvent. The fluid is applied, and the solvent evaporates leaving behind an oil film. However, it does not ’bond’ with the record. Perfluorinated products are some of the most stable products known, which is why they are now also known as "forever chemicals". However, there should be no health concerns with using LAST provided you do not drink it. The oil definitely plates out on the record, and it does not evaporate (perfluorinated oils are used in satellites) and once on the surface, as you have experienced, is not easily removed. Forget ultrasonics, multiple applications of a fairly aggressive detergent and vigorous brushing are what it takes to remove.