well it was just me and a 44th level warrior in solusek's eye B, taking on
some greater kobolds, and we decided to test which battle songs are most
effective. the results were:

once you get to level 36, dump anthem de arms. we found it to be very
ineffective, not very fast, and just a bit more STR than the other tests.
at level 36, stack Chant of Battle and Verses of Celerity, and give your
group an AC, STR, DEX, and AGI boost, as well as attack speed.

now that we knew anthem sucked at higher levels, the question was at level
42, to play Berserker Crescendo (which stacks with no other songs) or the
Chant/Celerity combo.
it is still a question, some people prefer one over the other. what we
could discern was that Berserker made you hit for your max dmg more often,
along with some increase in attack speed. it worked really well with my
warrior's executioner's axe, so he could hit for 80+ more often. but the
Chant/Celerity combo gives you a bit of everything, including attack speed
and getting hit less yourself, and we deduced that it would be better for
duel wielding, while Berserker may be more suited for 2h weps. If I was to
equip a brass instrument to double the effects of Berserker, it may make the
Chant/Celerity combo obsolete, but then i could not get in the fight, and
where's the fun in that?
i will add one other benefit of berserker is that you are only singing one
battle song instead of stacking two, which gives you the opportunity to play
a second song more easily.

i would love to hear any comments or further input that anyone has.

Shada Silverleaf, Level 45 Bard, Mithaniel Marr