For a comparison, typical values for water content on Earth are in the 15 to 50% range for the inhabited world. This is kind of an awkward way to present this

For a comparison, typical values for water content on Earth are in the 15 to 50% range for the inhabited world. This is kind of an awkward way to present this data. They are talking about water content (which is by weight) and then translating to volumes which is not straight-forward in all cases. I don't know how revolutionary this is. A cubic foot of soil is, in my experience, quite a bit larger than most laymen think and heating something a "couple hundred degrees" on a world with no established infrastructure (e.g. - there are no large scale solar panels or nuclear reactors set up on Mars) seems like quite a problem.