I soaked them for 48 hours and , yes, it did soften them up. However what I have found is that before the "treatment" the boots were somewhat flexible, not like new obviously with certain spots being rock hard. The dipping softened the areas that were already reasonably/somewhat flexible but did not help the areas that were rock hard. These previously hard areas seem to have been permanently altered and will not come back to a soft state.
All in all, if your boots are somewhat flexible I would say a 48 hour or longer soaking would help them. I dont know how long they will stay soft like this, they may "dry out" again quickly but it DID help them.
The only real solution I would be confident in is repleacing them with new ones for long term piece of mind but if you have things torn apart already and dont plan on changing them yet a dip would not hurt IMO. I would not go out of my way to perform this tho.
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