Bruce,
I supposed the answer would be a little inconvenient truth. I will follow your wise words.
Thanks, euG
Eugenio,
I am afraid that the question, as posed, is somewhat unanswerable.
Careful alignment (preferably to a reference) is essential and you
should take care to use the same parameters for every data set. I
don't know how to advise you about "rightness", but consistency is
certainly a must-do.
If you are looking at subtle changes in the XANES features, you might
consider turning off the "flattening" display trick that Athena uses
for displaying XANES data.
HTH,
B