No lying  here...if youve forgotten your highschool chemistry? its a
quite simple procedure...just apply a DC electric current to ordinary
tap water and it separates into oxygen and hydrogen.which go into twp
separate containers.

Where does the DC current come from ?,the alternator which converts AC
current to DC through the use of diodes.(Wheatstone Bridge).

This is an entirely possible and practical application for a very
simple procedure .

I doubt if shes lying because it is very POSSIBLE TO DO.

Of course you have tried this method ?

There is SOME loss of energy related to the driving of the alternator ,
(otherwise we would have perpetual motion) but unless you have
ACTUALLY tried this you will never know for sure how much your mileage
will increase or decrease?

Since hydrogen is EXTREMELY COMBUSTIBLE, ESPECIALLY IN THE PRESENCE OF
OXYGEN, it would seem within the realm of possibility that the mileage
would be increased

Whether it doubles or NOT is hard to say without empirical testing of
the sytem, but lets just say her mileage increase by 20 %? which would
be a nominal increase ? then the system would APPEAR to work as
designed.

Whether she gets double the mileage is moot until tests have been
conducted.But her mileage WOULD INCREASE.

And do you really think auto manufacturers are that concerned with gas
mileage ?

Do you know how many auto companies own stock in oil companies ?Much
as Ford in the 70`s owned stock in the salt mines , salt that is used
on roads in the north in  the winter.

Of course Ford cars rusted out quickly back then, primarily because
Ford used second grade steel in the production of their autos and the
addition of salt on the roads,only hastened the process

All theyre concerned with is sales and if gas guzzling vehicles are
still purchased by the public they will still keep building them.

They have had, since the early 70`s , (35 years)when we had the first
so-called energy shortage to improve gas muileage in their vehicles
and only RECENTLY have they paid any attention .

They still fight tooth and nail against any government proposed
legislation to improve mileage.

If they were TRULY interested in increased mileage ? they wouldnt NEED
the government to tell them what to do.