The testing I did for that post was literally done ingame, with the widgets using XIV-APP, and my TI89.
A lot of this has already been tested in a similar manner by Valk at http://valk.dancing-mad.com/. His manner of testing was to state that 1 damage = 1 hate, then had a tank class use a combo on a dummy, record the damage, and then see how much damage a dps class had to do the pull aggro.

Same idea here, but XIV-APP lets me see the damage and enmity values directly.